0001509991-26-000049 | 10-Q | XBRL Viewer

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Income Taxes - Schedule of Income (Loss) Before Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Income Tax Disclosure [Abstract]
United States	$ 14,647	$ (43,691)	$ (36,949)	$ (104,461)
Foreign	267,826	(20,069)	78,335	(53,330)
Income (loss) before income taxes	$ 282,473	$ (63,760)	$ 41,386	$ (157,791)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-30

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 4: http://www.xbrl.org/2003/role/exampleRef
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Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 220
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-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476153/220-40-55-4

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Topic 220
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476153/220-40-55-21

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476153/220-40-55-14

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478671/942-235-S50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477314/942-235-S99-1

Reference 10: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
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-Name Accounting Standards Codification
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-Paragraph 48
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-48

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 270
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482964/270-10-50-1

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (ee)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(11))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1

Reference 14: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-31

Reference 15: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

Reference 16: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

+ Details

Receivables - Schedule of Receivables (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Receivables [Abstract]
Joint interest billings, net	$ 13,780	$ 17,255
Oil and gas sales	90,369	56,700
Other current receivables	8,873	29,517
Total receivables	113,022	103,472
Long-term receivables	$ 472,897	$ 458,793

Accounting Policies

6 Months Ended

Jun. 30, 2026

Accounting Policies [Abstract]

Accounting Policies

General

The interim consolidated financial statements included in this report are unaudited and, in the opinion of management, include all adjustments of a normal recurring nature necessary for a fair presentation of the results for the interim periods. The results of the interim periods shown in this report are not necessarily indicative of the final results to be expected for the full year. The interim consolidated financial statements were prepared in accordance with the requirements of the SEC for interim reporting. As permitted under those rules, certain notes or other financial information that are normally required by GAAP have been condensed or omitted from these interim consolidated financial statements. These interim consolidated financial statements and the accompanying notes should be read in conjunction with our audited consolidated financial statements for the year ended December 31, 2025, included in our annual report on Form 10-K.

Reclassifications

Certain prior period amounts have been reclassified to conform with the current presentation. Such reclassifications had no significant impact on our reported net income (loss), current assets, total assets, current liabilities, total liabilities, stockholders’ equity or cash flows.

Cash, Cash Equivalents and Restricted Cash


	June 30, 2026		December 31, 2025
	(In thousands)
Cash and cash equivalents	$	102,137	$	91,518

Restricted cash - current	23,505		—
Restricted cash - long-term	30,589		26,226
Total cash, cash equivalents and restricted cash in the consolidated statements of cash flows	$	156,231	$	117,744

Cash and cash equivalents include demand deposits and funds invested in highly liquid instruments with original maturities of three months or less at the date of purchase. When our debt cover ratio exceeds 2.50x, we are required under the Facility to maintain a restricted cash balance that is sufficient to meet the payment of interest and fees for the next six-month period on the 7.750% Senior Notes, the 7.500% Senior Notes, the 8.750% Senior Notes and the 3.125% Convertible Senior Notes or the Facility, whichever is greater. During the first quarter of 2025, the Facility lenders waived the requirement to

maintain a restricted cash balance until the March 31, 2026 financial covenant test date. During the second quarter of 2026, the Facility lenders agreed to reduce the amount of the required restricted cash balance to three months of interest and fees until the September 30, 2026 financial covenant test date, after which the amount of the required restricted cash balance will be determined as usual. Our debt cover ratio for the most recent March 31, 2026 financial covenant test date exceeded 2.50x and the estimated restricted cash funding requirement is approximately $23.5 million. As of June 30, 2026, we have funded approximately $23.5 million into the debt service reserve account as required under the terms of the Facility. Restricted cash – long-term primarily represents cash and cash equivalents collateralized, in accounts held by us, as required to support existing performance obligations in the Gulf of America.

Inventories

Inventories consisted of $132.4 million and $144.9 million of materials and supplies and $7.5 million and $27.7 million of hydrocarbons as of June 30, 2026 and December 31, 2025, respectively. The Company’s materials and supplies inventory primarily consists of casing and wellheads and is stated at the lower of cost, using the weighted average cost method, or net realizable value.

Hydrocarbon inventory is carried at the lower of cost, using the weighted average cost method, or net realizable value. Hydrocarbon inventory costs include expenditures and other charges incurred in bringing the inventory to its existing condition. Selling expenses and general and administrative expenses are reported as period costs and excluded from inventory costs.

Assets and Liabilities Held for Sale

The Company classifies disposal groups as held for sale in the period in which all of the following criteria are met: (1) management, having the authority to approve the action, commits to a plan to sell the disposal group; (2) the disposal group is available for immediate sale in its present condition subject only to terms that are usual and customary for sales of such disposal groups; (3) an active program to locate a buyer or buyers and other actions required to complete the plan to sell the disposal group have been initiated; (4) the sale of the disposal group is probable, and the transfer of the disposal group is expected to qualify for recognition as a completed sale, within one year, except if events or circumstances beyond the Company’s control extended the period of time required to sell the disposal group beyond one year; (5) the disposal group is being actively marketed for sale at a price that is reasonable in relation to its current fair value; and (6) actions required to complete the plan indicate that it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn.

A disposal group that is classified as held for sale is initially measured at the lower of its carrying amount or fair value less any costs to sell. Any loss resulting from this measurement is recognized in the period in which the held for sale criteria are met. Subsequent changes in fair value of a disposal group less any costs to sell are reported as an adjustment to the carrying amount of the disposal group, as long as the new carrying amount does not exceed the carrying amount of the assets at the time it was initially classified as held for sale. Depreciation, depletion and amortization expense is not recorded on assets to be divested once they are classified as held for sale. In the initial period in which the disposal group meets the criteria to be classified as held for sale, the assets and liabilities of the disposal group are separately presented as assets held for sale and liabilities held for sale, respectively, in the Consolidated Balance Sheets.

Revenue Recognition

Our oil and gas revenues are recognized when hydrocarbons have been sold to a purchaser at a fixed or determinable price, title has transferred and collection is probable. Certain revenues are based on contracts with provisional pricing and quantity optionality which contain a derivative that is separated from the host contract for accounting purposes. The host contract is the receivable from sales at the spot price on the date of sale. The derivative, which is not designated as a hedge, is marked to market through oil and gas revenue each period until the final settlement occurs, which generally is limited to the month of or month after the sale.

Oil and gas revenue is composed of the following:


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
	(In thousands)
Revenues from contracts with customers:
Ghana	$	365,880	$	212,880	$	616,032	$	365,685
Equatorial Guinea	47,464		63,196		71,951		96,878
Mauritania\|Senegal	93,596		20,239		145,862		22,936
Gulf of America	111,439		103,100		206,241		204,878
Total revenues from contracts with customers	618,379		399,415		1,040,086		690,377
Provisional sales contracts	(11,126)		(6,780)		(62,105)		(7,607)
Oil and gas revenue	$	607,253	$	392,635	$	977,981	$	682,770

Concentration of Credit Risk

Our revenue can be materially affected by current economic conditions and the price of oil and natural gas. However, based on the current demand for crude oil and natural gas and the fact that alternative purchasers are readily available, we believe that the loss of our purchasers and/or of the purchasers identified by our marketing agents would not have a long‑term material adverse effect on our financial position or results of Ghana operations. Customers in our Gulf of America and Mauritania | Senegal business units that comprise 10% or more of our total consolidated oil and gas revenue for the three and six months ended June 30, 2026 and 2025, are shown below.


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
	(Percentage)
Customer
BP plc	77	%	18	%	62	%	19	%
Shell Trading (US) Company	18	%	4	%	20	%	5	%

Recent Accounting Standards

Not Yet Adopted

In November 2024, the FASB issued ASU 2024-03, “Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses”. The amendments in ASU 2024-03 require more detailed disclosures about specified categories of costs and expenses included in certain expense captions presented on the face of the income statement. This ASU is effective for fiscal years beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. The Company is currently assessing the impact of this standard on its financial statement disclosures.

In November 2024, the FASB issued ASU 2024-04, “Debt - Debt with Conversion and Other Options (Subtopic 470-20): Induced Conversions of Convertible Debt Instruments.” The amendments in ASU 2024-04 clarify the requirements for determining whether certain settlements of convertible debt instruments should be accounted for as an induced conversion. The amendments in the ASU are effective for annual periods beginning after December 15, 2025. Early adoption is permitted, however, we do not plan to early adopt ASU 2024-04. The Company is currently assessing the impact this standard will have on its consolidated financial statements.

Organization	6 Months Ended
Organization	Jun. 30, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Organization Kosmos Energy Ltd. is incorporated in the State of Delaware as a holding company for Kosmos Energy Delaware Holdings, LLC, a Delaware limited liability company. As a holding company, Kosmos Energy Ltd.’s management operations are conducted through a wholly-owned subsidiary, Kosmos Energy, LLC. The terms “Kosmos,” the “Company,” “we,” “us,” “our,” “ours,” and similar terms refer to Kosmos Energy Ltd. and its wholly-owned subsidiaries, unless the context indicates otherwise. Kosmos Energy is a leading deepwater exploration and production company focused on meeting the world’s growing demand for energy. We have diversified oil and gas production from assets offshore Ghana, Mauritania, Senegal and the Gulf of America. Additionally, in the proven basins where we operate, we are advancing high-quality development opportunities which have come from our exploration success. Kosmos is listed on the NYSE and LSE and is traded under the ticker symbol KOS. Kosmos is engaged in a single line of business, which is the exploration, development, and production of oil and natural gas. Substantially all of our long-lived assets and all of our product sales are related to operations in three geographic areas: Ghana, Mauritania/Senegal and the Gulf of America.

Derivative Financial Instruments - Narrative (Details) - Dated Brent - Two-Way Collars - Subsequent Event MBbls in Millions	1 Months Ended
	Jul. 31, 2026 $ / bbl MBbls
January 2027 through December 2027
Derivative Financial Instruments
Volume (mbbls) \| MBbls	2.0
Term January 2027 To December 2027
Derivative Financial Instruments
Floor (usd per bbl)	67.50
Ceiling (usd per bbl)	90.00

Fair Value Measurements - Schedule of Carrying Values and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Jan. 31, 2026	Dec. 31, 2025	Dec. 31, 2024	Sep. 30, 2024	Mar. 31, 2024	Oct. 31, 2021	Mar. 31, 2021	Apr. 30, 2019
Carrying Value
Fair Value Measurements
Long-term debt	$ 2,707,731		$ 3,085,786
Fair Value
Fair Value Measurements
Long-term debt	2,512,807		2,497,101
7.125% Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)									7.125%
7.125% Senior Notes \| Senior Notes \| Carrying Value
Fair Value Measurements
Long-term debt	0		99,942
7.125% Senior Notes \| Senior Notes \| Fair Value
Fair Value Measurements
Long-term debt	0		99,303
7.750% Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)							7.75%
7.750% Senior Notes \| Senior Notes \| Carrying Value
Fair Value Measurements
Long-term debt	99,747		348,757
7.750% Senior Notes \| Senior Notes \| Fair Value
Fair Value Measurements
Long-term debt	99,456		321,394
7.500% Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)								7.50%
7.500% Senior Notes \| Senior Notes \| Carrying Value
Fair Value Measurements
Long-term debt	398,825		398,426
7.500% Senior Notes \| Senior Notes \| Fair Value
Fair Value Measurements
Long-term debt	381,313		270,125
8.750% Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)					8.75%
8.750% Senior Notes \| Senior Notes \| Carrying Value
Fair Value Measurements
Long-term debt	495,866		495,564
8.750% Senior Notes \| Senior Notes \| Fair Value
Fair Value Measurements
Long-term debt	$ 409,555		$ 283,575
3.125% Convertible Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)	3.125%		3.125%	3.125%		3.125%
3.125% Convertible Senior Notes \| Senior Notes \| Carrying Value
Fair Value Measurements
Long-term debt	$ 393,864		$ 393,097
3.125% Convertible Senior Notes \| Senior Notes \| Fair Value
Fair Value Measurements
Long-term debt	293,572		172,704
11.250% Senior Secured Bonds \| Senior Secured Bond
Fair Value Measurements
Interest rate (as a percent)		11.25%
11.250% Senior Secured Bonds \| Senior Secured Bond \| Carrying Value
Fair Value Measurements
Long-term debt	350,000		0
11.250% Senior Secured Bonds \| Senior Secured Bond \| Fair Value
Fair Value Measurements
Long-term debt	359,482		0
GoA Term Loan Facility \| Secured Debt \| Carrying Value
Fair Value Measurements
Long-term debt	196,429		150,000
GoA Term Loan Facility \| Secured Debt \| Fair Value
Fair Value Measurements
Long-term debt	196,429		150,000
Facility \| Revolving Credit Facility \| Carrying Value
Fair Value Measurements
Long-term debt	773,000		1,200,000
Facility \| Revolving Credit Facility \| Fair Value
Fair Value Measurements
Long-term debt	$ 773,000		$ 1,200,000

Net Income (Loss) Per Share - Narrative (Details) $ / shares in Units, shares in Millions, $ in Millions	Mar. 10, 2026 USD ($) $ / shares shares
Earnings Per Share [Abstract]
Number of shares issued (in shares) \| shares	112.1
Sale of stock, par value (in dollars per share) \| $ / shares	$ 0.01
Proceeds from issuance \| $	$ 206.4

Receivables - Narrative (Details) - National Oil Companies of Mauritania And Senegal - Carry Advance Agreements - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Oil and Gas Joint Interest Billing Receivables [Line Items]
Long-term receivables	$ 450.9		$ 450.9		$ 437.1
Interest income, long-term notes receivable	$ 7.0	$ 6.2	$ 13.8	$ 11.5

Leases

6 Months Ended

Jun. 30, 2026

Leases [Abstract]

Leases

We have commitments under operating leases primarily related to office leases and as well as the commitment under the TEN FPSO finance lease. Our leases have initial lease terms ranging from one year to ten years. Certain lease agreements contain provisions for future rent increases.

Other information related to operating and finance leases at June 30, 2026 and December 31, 2025, is as follows:


	June 30, 2026		December 31, 2025
	(In thousands, except lease term discount rate)
Balance sheet classifications
Operating leases
Other assets (right-of-use assets)	$	8,705	$	10,059
Accrued liabilities (current maturities of leases)	3,060		2,777
Other long-term liabilities (non-current maturities of leases)	7,852		9,438
Finance leases
Property and equipment, net(1)	69,454		—
Accrued liabilities	73,203		—

(1) Represents $88.2 million of proved property additions or our proportionate share of the TEN FPSO finance lease asset offset by depletion expense of approximately $18.7 million for the period ended June 30, 2026.

Future minimum rental commitments under our leases as of June 30, 2026, are as follows:


	Operating Leases(1)		Financing Leases(1)
	(In thousands)
2026(2)	$	2,017	$	24,504
2027	3,951		52,514
2028	3,744		—
2029	3,176		—
2030	—		—
Thereafter	—		—
Total undiscounted lease payments	$	12,888	$	77,018
Less: Imputed interest	(1,976)		(3,815)
Total lease liabilities	$	10,912	$	73,203

__________________________________

(1) Does not include purchase commitments for jointly owned fields and facilities where we are not the operator and excludes commitments for exploration activities, including well commitments, in our petroleum contracts.

(2) Represents the period July 1, 2026 through December 31, 2026

Leases

Other information related to operating and finance leases at June 30, 2026 and December 31, 2025, is as follows:


	June 30, 2026		December 31, 2025
	(In thousands, except lease term discount rate)
Balance sheet classifications
Operating leases
Other assets (right-of-use assets)	$	8,705	$	10,059
Accrued liabilities (current maturities of leases)	3,060		2,777
Other long-term liabilities (non-current maturities of leases)	7,852		9,438
Finance leases
Property and equipment, net(1)	69,454		—
Accrued liabilities	73,203		—

Future minimum rental commitments under our leases as of June 30, 2026, are as follows:


	Operating Leases(1)		Financing Leases(1)
	(In thousands)
2026(2)	$	2,017	$	24,504
2027	3,951		52,514
2028	3,744		—
2029	3,176		—
2030	—		—
Thereafter	—		—
Total undiscounted lease payments	$	12,888	$	77,018
Less: Imputed interest	(1,976)		(3,815)
Total lease liabilities	$	10,912	$	73,203

__________________________________

(2) Represents the period July 1, 2026 through December 31, 2026

Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2026

Accounting Policies [Abstract]

General

Reclassifications

Cash, Cash Equivalents and Restricted Cash

Inventories

The Company’s materials and supplies inventory primarily consists of casing and wellheads and is stated at the lower of cost, using the weighted average cost method, or net realizable value.

Assets and Liabilities Held for Sale

Revenue Recognition

Concentration of Credit Risk


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
	(Percentage)
Customer
BP plc	77	%	18	%	62	%	19	%
Shell Trading (US) Company	18	%	4	%	20	%	5	%

Recent Accounting Standards

Not Yet Adopted

Fair Value Measurements

In accordance with ASC 820 — Fair Value Measurement, fair value measurements are based upon inputs that market participants use in pricing an asset or liability, which are classified into two categories: observable inputs and unobservable inputs. Observable inputs represent market data obtained from independent sources, whereas unobservable inputs reflect a company’s own market assumptions, which are used if observable inputs are not reasonably available without undue cost and effort. We prioritize the inputs used in measuring fair value into the following fair value hierarchy:

•Level 1 — quoted prices for identical assets or liabilities in active markets.

•Level 2 — quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability and inputs derived principally from or corroborated by observable market data by correlation or other means.

•Level 3 — unobservable inputs for the asset or liability. The fair value input hierarchy level to which an asset or liability measurement in its entirety falls is determined based on the lowest level input that is significant to the measurement in its entirety.

Suspended Well Costs (Tables)

6 Months Ended

Jun. 30, 2026

Oil and Gas Disclosure [Abstract]

Schedule of Capitalized Exploratory Well Costs

The following table reflects the Company’s capitalized exploratory well costs on drilled wells as of and during the six months ended June 30, 2026.


	June 30, 2026
	(In thousands)
Beginning balance	$	73,141
Additions to capitalized exploratory well costs pending the determination of proved reserves	4,985
Reclassification due to determination of proved reserves	—
Capitalized exploratory well costs charged to expense	—
Ending balance	$	78,126

Schedule of Aging of Capitalized Exploratory Well Costs and Number of Projects for Which Exploratory Well Costs were Capitalized for More Than One Year

The following table provides an aging of capitalized exploratory well costs based on the date drilling was completed and the number of projects for which exploratory well costs have been capitalized for more than one year since the completion of drilling:


	June 30, 2026		December 31, 2025
	(In thousands, except project counts)
Exploratory well costs capitalized for a period of one year or less	$	—	$	—
Exploratory well costs capitalized for a period of one to five years	78,126		73,141
Exploratory well costs capitalized for a period of six to ten years	—		—
Ending balance	$	78,126	$	73,141
Number of projects that have exploratory well costs that have been capitalized for a period greater than one year	1		1

Accounting Policies - Schedule of Oil and Gas Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation of Revenue [Line Items]
Provisional sales contracts	$ 40,683	$ 15,469	$ (262,292)	$ 7,883
Oil and gas revenue	607,253	392,635	977,981	682,770
Oil and gas revenue
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	618,379	399,415	1,040,086	690,377
Provisional sales contracts	(11,126)	(6,780)	(62,105)	(7,607)
Oil and gas revenue	607,253	392,635	977,981	682,770
Ghana \| Oil and gas revenue
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	365,880	212,880	616,032	365,685
Equatorial Guinea \| Oil and gas revenue
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	47,464	63,196	71,951	96,878
Mauritania\|Senegal \| Oil and gas revenue
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	93,596	20,239	145,862	22,936
Gulf of America \| Oil and gas revenue
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	$ 111,439	$ 103,100	$ 206,241	$ 204,878

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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+ Details

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

+ Details

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details

Equity-based Compensation (Tables)

6 Months Ended

Jun. 30, 2026

Share-Based Payment Arrangement [Abstract]

Schedule of Outstanding Restricted Stock Units

The following table reflects the outstanding restricted stock units as of June 30, 2026:


		Weighted-		Market / Service	Weighted-
	Service Vesting	Average		Vesting	Average
	Restricted Stock	Grant-Date		Restricted Stock	Grant-Date
	Units	Fair Value		Units	Fair Value
	(In thousands)			(In thousands)
Outstanding at December 31, 2025	5,073	$	4.59	8,105	$	8.43
Granted(1)	5,275	1.26		4,238	1.96
Forfeited(1)	(864)	1.21		(254)	4.37
Vested	(2,824)	4.47		(590)	12.25
Outstanding at June 30, 2026	6,660	$	2.80	11,499	$	4.26

__________________________________

(1)The restricted stock units with a combination of market and service vesting criteria may vest between 0% and 200% of the originally granted units depending upon market performance conditions. Awards vesting over or under target shares of 100% results in additional shares granted or forfeited, respectively, in the period the market vesting criteria is determined.

Organization (Details)	6 Months Ended
Organization (Details)	Jun. 30, 2026 segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating geographic areas	3

Net Income (Loss) Per Share (Tables)

6 Months Ended

Jun. 30, 2026

Earnings Per Share [Abstract]

Schedule of Reconciliation Between Compute Basic and Diluted Net Loss Per Share and Weighted Average Share Outstanding

The following table is a reconciliation between net income (loss) and the amounts used to compute basic and diluted net income (loss) per share and the weighted average shares outstanding used to compute basic and diluted net income (loss) per share. Potentially dilutive securities include shares issuable upon conversion of our 3.125% Convertible Senior Notes using the if-converted method and restricted stock units awards under our equity-based compensation plan.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
	(In thousands, except per share data)
Numerator:
Net income (loss) allocable to common stockholders	$	184,775	$	(87,740)	$	(40,799)	$	(198,346)




Denominator:
Weighted average number of shares outstanding:
Basic	593,441		478,068		550,060		476,881
Restricted stock units(1)	11,272		—		—		—
Shares issuable assuming conversion of 3.125% Convertible Senior Notes(2)	—		—		—		—
Diluted	604,713		478,068		550,060		476,881
Net income (loss) per share:
Basic	$	0.31	$	(0.18)	$	(0.07)	$	(0.42)
Diluted	$	0.31	$	(0.18)	$	(0.07)	$	(0.42)

__________________________________

(1)We excluded restricted stock units of 2.5 million and 5.2 million for the three months ended June 30, 2026 and 2025, respectively, and 17.1 million and 5.9 million for the six months ended June 30, 2026 and 2025, respectively from the computations of diluted net income (loss) per share because the effect would have been anti-dilutive.

(2)Represents the dilutive impact for the Company’s 3.125% Convertible Senior Notes due 2030. As of June 30, 2026, the if-converted value is less than the outstanding principal of the 3.125% Convertible Senior Notes and therefore anti-dilutive. The 3.125% Convertible Senior Notes are subject to a capped call arrangement that potentially reduces the dilutive effect. Any potential impact of the capped call arrangement is excluded from this table as any proceeds under the capped call arrangement are considered anti-dilutive.

Income Taxes (Tables)

6 Months Ended

Jun. 30, 2026

Income Tax Disclosure [Abstract]

Schedule of Components of Income (Loss) Before Income Taxes

Income (loss) before income taxes is composed of the following:


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
	(In thousands)
United States	$	14,647	$	(43,691)	$	(36,949)	$	(104,461)
Foreign (1)	267,826		(20,069)		78,335		(53,330)
Income (loss) before income taxes	$	282,473	$	(63,760)	$	41,386	$	(157,791)

(1) Foreign tax expense includes amounts related to Ceiba and Okume Complex located in Block G offshore Equatorial Guinea through the date of sale in June 2026. See Note 3 - Acquisitions and Divestitures for additional information.

Additional Financial Information - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Accrued liabilities:
Exploration, development and production	$ 43,793	$ 57,007
Revenue payable	18,862	69,273
Current asset retirement obligations	9,767	10,481
Finance lease liability	73,203	0
General and administrative expenses	23,460	4,916
Interest	91,427	67,830
Income taxes	51,596	16,050
Taxes other than income	2,209	1,305
Derivatives	14,921	125
Other	14,641	10,622
Accrued liabilities	$ 343,879	$ 237,609

Acquisitions and Divestitures

6 Months Ended

Jun. 30, 2026

Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]

Acquisitions and Divestitures

On February 24, 2026, the Company entered into a Share Sale and Purchase Agreement with a subsidiary of Panoro Energy ASA for the sale of all of our 40.4% participating interest in the Ceiba Field and Okume Complex production assets located in Block G offshore Equatorial Guinea. The transaction closed on June 16, 2026.

Pursuant to the terms of the purchase agreement, Kosmos received final cash consideration of approximately $127.0 million, based on the initial purchase price of $180.0 million reduced by certain purchase price adjustments totaling approximately $53.0 million. The Company is also entitled to future contingent consideration of up to $39.5 million, comprised of $12.5 million linked to future production performance at the Ceiba field, and $9.0 million payable in each of the years 2027, 2028 and 2029, subject to certain production and oil price thresholds.

The proceeds from the transaction were used to repay borrowings under the Facility in June 2026.

Management considers the assets and liabilities in the Ceiba Field and Okume Complex production assets located in Block G offshore Equatorial Guinea included in the Share Sale and Purchase Agreement as a disposal group. The disposal group had previously been classified as held for sale. The following table summarizes the carrying amounts of the major classes of assets and liabilities included in the disposal group as of the date of sale:


	As of date of sale
	(In thousands)
Assets
Current assets:
Cash and cash equivalents	$	—
Receivables	—
Inventories	9,100
Prepaid expenses and other	737
Total current assets	9,837

Non-current assets:
Property and equipment, net	410,458
Total non-current assets	410,458
Total assets of disposal group	$	420,295

Liabilities
Current liabilities:
Accounts Payable	$	34,376
Accrued Liabilities	—
Total current liabilities	34,376

Long-term Liabilities
Asset retirement obligations	142,211
Deferred tax liabilities	126,092
Total long-term liabilities	268,303
Total liabilities of disposal group	$	302,679

Upon closing, the Company recognized a gain on sale of assets of approximately $9.4 million, representing the excess of net proceeds received over the carrying value of the disposal group. The Company evaluated the future contingent consideration and determined that no amounts were recognized at closing as realization is contingent upon future production and commodity price conditions. Any contingent consideration will be recognized when realized. The divestiture does not meet the criteria to be reported as discontinued operations as it does not represent a strategic shift for the Company. Accordingly, the operating results for the disposal group are included in continuing operations in the Company’s Consolidated Statement of Operations through the date of sale in June 2026.

Debt (Tables)

6 Months Ended

Jun. 30, 2026

Debt Disclosure [Abstract]

Schedule of Debt


	June 30, 2026		December 31, 2025
	(In thousands)
Outstanding debt principal balances:
Facility	$	773,000	$	1,200,000
7.125% Senior Notes	—		100,000
7.750% Senior Notes	99,973		350,000
7.500% Senior Notes	400,274		400,274
8.750% Senior Notes	500,000		500,000
3.125% Convertible Senior Notes	400,000		400,000
11.250% Senior Secured Bonds	350,000		—
GoA Term Loan Facility	196,429		150,000
Total long-term debt	2,719,676		3,100,274
Unamortized deferred financing costs and discounts(1)	(47,501)		(47,515)
Total debt, net	2,672,175		3,052,759
Less: Current maturities of long-term debt	(145,303)		(132,143)
Long-term debt, net	$	2,526,872	$	2,920,616

(1)Includes $21.7 million and $24.3 million of unamortized deferred financing costs related to the Facility, $8.0 million and $10.4 million of unamortized deferred financing costs and discounts related to the Senior Notes, and $8.0 million and $9.0 million of unamortized deferred financing costs related to the 3.125% Convertible Senior Notes, $6.3 million and $0.8 million of unamortized deferred financing costs related to the 11.250% Senior Secured Bonds and $3.5 million and $3.0 million of unamortized deferred financing costs related to the GoA Term Loan Facility as of June 30, 2026 and December 31, 2025, respectively.

Schedule of Redemption Price

On and after July 29, 2028, the Company may redeem all or part of the GTA Nordic bonds at the following redemption prices (expressed as a percentage of principal amount), plus accrued and unpaid interest, if any, on the notes redeemed:


Year	Percentage
July 29, 2028 to, but not including, July 29, 2029	105.625	%
July 29, 2029 to, but not including, July 29, 2030	103.375	%
July 29, 2030 and thereafter	100.000	%

Schedule of Estimated Repayments of Debt

At June 30, 2026, the estimated repayments of debt during the five fiscal year periods and thereafter are as follows:


	Payments Due by Year
	Total		2026(2)		2027		2028		2029		2030		Thereafter
	(In thousands)
Principal debt repayments(1)	$	2,719,676	$	15,110	$	304,848	$	718,857	$	430,861	$	400,000	$	850,000

__________________________________

(1)Includes the scheduled maturities for outstanding principal debt balances. The scheduled maturities of debt related to the Facility as of June 30, 2026 are based on our level of borrowings and our estimated future available borrowing base commitment levels in future periods. Any increases or decreases in the level of borrowings or increases or decreases in the available borrowing base would impact the scheduled maturities of debt during the next five years and thereafter.

(2)Represents payments for the period July 1, 2026 through December 31, 2026.

Schedule of Interest and Other Financing Costs, Net

Interest and other financing costs, net incurred during the periods is comprised of the following:


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
	(In thousands)
Interest expense	$	60,995	$	55,825	$	122,051	$	111,671
Amortization—deferred financing costs	2,705		1,889		5,297		3,773
Debt modifications and extinguishments	136		—		(1,081)		—
Capitalized interest	(2,229)		(4,316)		(4,096)		(8,510)
Deferred interest	(8,239)		249		(10,954)		(1,793)
Interest income	(8,265)		(7,158)		(16,140)		(15,253)
Other, net	8,597		8,345		17,425		16,788
Interest and other financing costs, net	$	53,700	$	54,834	$	112,502	$	106,676

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 13: http://www.xbrl.org/2009/role/commonPracticeRef
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-URI https://asc.fasb.org/1943274/2147477734/942-470-50-3

+ Details

Accounting Policies - Schedule of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025	Dec. 31, 2024
Accounting Policies [Abstract]
Cash and cash equivalents	$ 102,137	$ 91,518
Restricted cash - current	23,505	0
Restricted cash - long-term	30,589	26,226
Total cash, cash equivalents and restricted cash in the consolidated statements of cash flows	$ 156,231	$ 117,744	$ 51,999	$ 85,277

Acquisitions and Divestitures - Schedule of Major Classes of Assets and Liabilities (Details) - Disposal Group, Disposed of by Sale, Not Discontinued Operations $ in Thousands	Jun. 30, 2026 USD ($)
Current assets:
Cash and cash equivalents	$ 0
Receivables	0
Inventories	9,100
Prepaid expenses and other	737
Total current assets	9,837
Non-current assets:
Property and equipment, net	410,458
Total non-current assets	410,458
Total assets of disposal group	420,295
Current liabilities:
Accounts Payable	34,376
Accrued Liabilities	0
Total current liabilities	34,376
Long-term Liabilities
Asset retirement obligations	142,211
Deferred tax liabilities	126,092
Total long-term liabilities	268,303
Total liabilities of disposal group	$ 302,679

Property and Equipment (Tables)

6 Months Ended

Jun. 30, 2026

Property, Plant, and Equipment [Abstract]

Schedule of Property and Equipment

Property and equipment is stated at cost and consisted of the following:


	June 30, 2026		December 31, 2025
	(In thousands)
Oil and gas properties:
Proved properties	$	7,763,259	$	8,301,679
Unproved properties	210,786		210,161
Total oil and gas properties	7,974,045		8,511,840
Accumulated depletion	(4,624,781)		(4,780,826)
Oil and gas properties, net	3,349,264		3,731,014

Other property	69,046		68,255
Accumulated depreciation	(66,784)		(65,485)
Other property, net	2,262		2,770

Property and equipment, net	$	3,351,526	$	3,733,784

Derivative Financial Instruments - Schedule of Oil Derivative Contracts (Details)	6 Months Ended
	Jun. 30, 2026 $ / bbl MBbls
Dated Brent \| Term July 2026 To Dec 2026 \| Three-way collars
Derivative Financial Instruments
Volume (mbbls) \| MBbls	1,000
Weighted Average Price per Bbl
Net deferred premium payable/(receivable) (usd per bbl)	0
Swap (usd per bbl)	0
Sold put (usd per bbl)	50.00
Floor (usd per bbl)	60.00
Ceiling (usd per bbl)	75.51
Dated Brent \| Term July 2026 To Dec 2026 \| Swaps
Derivative Financial Instruments
Volume (mbbls) \| MBbls	500
Weighted Average Price per Bbl
Net deferred premium payable/(receivable) (usd per bbl)	0
Swap (usd per bbl)	72.46
Sold put (usd per bbl)	0
Floor (usd per bbl)	0
Ceiling (usd per bbl)	100.00
Dated Brent \| Term July 2026 To Dec 2026 1 \| Swaps
Derivative Financial Instruments
Volume (mbbls) \| MBbls	1,000
Weighted Average Price per Bbl
Net deferred premium payable/(receivable) (usd per bbl)	0
Swap (usd per bbl)	69.70
Sold put (usd per bbl)	55.00
Floor (usd per bbl)	0
Ceiling (usd per bbl)	0
Dated Brent \| Term January 2027 To December 2027 \| Three-way collars
Derivative Financial Instruments
Volume (mbbls) \| MBbls	2,000
Weighted Average Price per Bbl
Net deferred premium payable/(receivable) (usd per bbl)	0.40
Swap (usd per bbl)	0
Sold put (usd per bbl)	47.50
Floor (usd per bbl)	60.00
Ceiling (usd per bbl)	75.00
Dated Brent \| Term January 2027 To June 2027 \| Three-way collars
Derivative Financial Instruments
Volume (mbbls) \| MBbls	2,000
Weighted Average Price per Bbl
Net deferred premium payable/(receivable) (usd per bbl)	0.03
Swap (usd per bbl)	0
Sold put (usd per bbl)	55.00
Floor (usd per bbl)	70.00
Ceiling (usd per bbl)	85.00
NYMEX WTI \| Term July 2026 To Dec 2026 1 \| Swaps
Derivative Financial Instruments
Volume (mbbls) \| MBbls	750
Weighted Average Price per Bbl
Net deferred premium payable/(receivable) (usd per bbl)	0
Swap (usd per bbl)	64.83
Sold put (usd per bbl)	50.00
Floor (usd per bbl)	0
Ceiling (usd per bbl)	0
NYMEX WTI \| Term January 2027 To December 2027 \| Three-way collars
Derivative Financial Instruments
Volume (mbbls) \| MBbls	1,000
Weighted Average Price per Bbl
Net deferred premium payable/(receivable) (usd per bbl)	0.50
Swap (usd per bbl)	0
Sold put (usd per bbl)	55.00
Floor (usd per bbl)	70.00
Ceiling (usd per bbl)	90.00

Fair Value Measurements - Schedule of Company's Assets and Liabilities (Details) - Recurring basis - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Liabilities:
Total derivatives not designated as hedging instruments	$ 22,541	$ 74,204
Quoted Prices in Active Markets for Identical Assets (Level 1)
Liabilities:
Total derivatives not designated as hedging instruments	0	0
Significant Other Observable Inputs (Level 2)
Liabilities:
Total derivatives not designated as hedging instruments	22,541	74,204
Significant Unobservable Inputs (Level 3)
Liabilities:
Total derivatives not designated as hedging instruments	0	0
Commodity derivatives
Assets:
Derivative asset, fair value	2,794	50,497
Liabilities:
Commodity derivatives	(16,762)
Commodity derivatives \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Derivative asset, fair value	0	0
Liabilities:
Commodity derivatives	0
Commodity derivatives \| Significant Other Observable Inputs (Level 2)
Assets:
Derivative asset, fair value	2,794	50,497
Liabilities:
Commodity derivatives	(16,762)
Commodity derivatives \| Significant Unobservable Inputs (Level 3)
Assets:
Derivative asset, fair value	0	0
Liabilities:
Commodity derivatives	0
Provisional sales contracts
Assets:
Derivative asset, fair value	857
Provisional sales contracts \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Derivative asset, fair value	0
Provisional sales contracts \| Significant Other Observable Inputs (Level 2)
Assets:
Derivative asset, fair value	857
Provisional sales contracts \| Significant Unobservable Inputs (Level 3)
Assets:
Derivative asset, fair value	0
Debt securities held in decommissioning trust fund
Assets:
Debt securities held in decommissioning trust fund	35,652	23,707
Debt securities held in decommissioning trust fund \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Debt securities held in decommissioning trust fund	0	0
Debt securities held in decommissioning trust fund \| Significant Other Observable Inputs (Level 2)
Assets:
Debt securities held in decommissioning trust fund	35,652	23,707
Debt securities held in decommissioning trust fund \| Significant Unobservable Inputs (Level 3)
Assets:
Debt securities held in decommissioning trust fund	$ 0	$ 0

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Jun. 30, 2026 shares
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Terminated	false
Sir John Grant [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	On May 27, 2026, Sir John Grant terminated a trading plan intended to satisfy the conditions under Rule 10b5-1(c) of the Exchange Act. Sir John Grant’s plan was previously adopted on March 4, 2026, for the sale of up to 43,466 shares of our common stock on June 3, 2026, in order to cover income tax liability from the vesting of restricted share units that were granted to him under the Company’s Long Term Incentive Plan. The plan was never utilized.
Name	Sir John Grant
Rule 10b5-1 Arrangement Terminated	true
Termination Date	May 27, 2026
Aggregate Available	43,466

Business Segment Information (Tables)

6 Months Ended

Jun. 30, 2026

Segment Reporting [Abstract]

Schedule of Business Segment Information

Financial information for each area is presented below:


	Ghana		Equatorial Guinea(2)		Mauritania/Senegal		Gulf of America		Corporate & Other		Eliminations		Total
	(In thousands)
Three Months Ended June 30, 2026
Revenues and other income:
Oil and gas revenue	$	356,595	$	47,161	$	92,058	$	111,439	$	—	$	—	$	607,253
Gain on sale of assets	—		9,421		—		—		—		—		9,421
Other income, net	361		—		—		46		131		(177)		361
Total revenues and other income	356,956		56,582		92,058		111,485		131		(177)		617,035
Costs and expenses:
Oil and gas production	59,031		25,244		65,827		29,327		—		—		179,429
Exploration expenses	(3)		146		238		2,653		163		—		3,197
General and administrative	3,227		1,003		2,710		4,886		41,984		(34,547)		19,263
Depletion, depreciation and amortization	54,075		2,611		35,221		27,740		854		—		120,501

Interest and other financing costs, net(1)	10,803		(22)		8,379		1,320		33,220		—		53,700
Derivatives, net	—		—		—		—		(51,809)		—		(51,809)
Other expenses, net	(21,970)		(226)		1,352		(4,662)		1,417		34,370		10,281
Total costs and expenses	105,163		28,756		113,727		61,264		25,829		(177)		334,562
Income (loss) before income taxes	251,793		27,826		(21,669)		50,221		(25,698)		—		282,473
Income tax expense	91,498		5,093		9		70		1,028		—		97,698
Net income (loss)	$	160,295	$	22,733	$	(21,678)	$	50,151	$	(26,726)	$	—	$	184,775

Consolidated capital expenditures	$	70,494	$	2,090	$	3,216	$	28,382	$	870	$	—	$	105,052


	Ghana		Equatorial Guinea(2)		Mauritania/Senegal		Gulf of America		Corporate & Other		Eliminations		Total
	(In thousands)
Six months ended June 30, 2026
Revenues and other income:
Oil and gas revenue	$	557,859	$	69,556	$	144,325	$	206,241	$	—	$	—	$	977,981
Gain on sale of assets	—		9,421		—		—		—		—		9,421
Other income, net	530		—		—		103		291,492		(291,595)		530
Total revenues and other income	558,389		78,977		144,325		206,344		291,492		(291,595)		987,932
Costs and expenses:
Oil and gas production	87,455		40,097		121,168		61,304		—		—		310,024
Exploration expenses	—		1,260		574		6,667		14,440		—		22,941
General and administrative	7,167		2,468		5,420		10,690		95,198		(73,970)		46,973
Depletion, depreciation and amortization	107,592		6,732		66,017		59,026		1,007		—		240,374

Interest and other financing costs, net(1)	22,566		(57)		13,960		3,694		72,339		—		112,502
Derivatives, net	—		—		—		—		200,187		—		200,187
Other expenses, net	132,978		67,842		2,077		25,829		2,444		(217,625)		13,545
Total costs and expenses	357,758		118,342		209,216		167,210		385,615		(291,595)		946,546
Income (loss) before income taxes	200,631		(39,365)		(64,891)		39,134		(94,123)		—		41,386
Income tax expense (benefit)	73,950		5,743		9		71		2,412		—		82,185
Net income (loss)	$	126,681	$	(45,108)	$	(64,900)	$	39,063	$	(96,535)	$	—	$	(40,799)

Consolidated capital expenditures, net	$	140,105	$	2,599	$	5,266	$	46,907	$	1,655	$	—	$	196,532

As of June 30, 2026
Property and equipment, net	$	1,001,641	$	13,999	$	1,846,885	$	487,042	$	1,959	$	—	$	3,351,526
Total assets	$	3,429,540	$	132,939	$	6,326,648	$	3,884,596	$	29,688,971	$	(39,152,547)	$	4,310,147

______________________________________

(1)Interest expense is recorded based on actual third-party and intercompany debt agreements. Capitalized interest is recorded on the business unit where the assets reside.

(2)In June 2026, the Company completed the disposition of its interests in the Ceiba Field and Okume Complex production assets located in Block G offshore Equatorial Guinea. The operating results of the Equatorial Guinea segment are included in the Company's consolidated results through the date of sale in June 2026. The disposition did not qualify for discontinued operations presentation. See Note 3 - Acquisitions and Divestitures for additional information.


	Ghana		Equatorial Guinea(2)		Mauritania/Senegal		Gulf of America		Corporate & Other		Eliminations		Total
	(In thousands)
Three months ended June 30, 2025
Revenues and other income:
Oil and gas revenue	$	204,706	$	64,590	$	20,239	$	103,100	$	—	$	—	$	392,635
Gain on sale of assets	—		—		—		600		—		—		600
Other income, net	246		—		—		219		13,880		(14,062)		283
Total revenues and other income	204,952		64,590		20,239		103,919		13,880		(14,062)		393,518
Costs and expenses:
Oil and gas production	95,357		39,957		69,141		38,663		—		—		243,118
Exploration expenses	24		(892)		2,119		2,649		169		—		4,069
General and administrative	2,904		1,150		2,575		3,269		44,804		(35,628)		19,074
Depletion, depreciation and amortization	43,624		27,468		12,677		67,364		135		—		151,268

Interest and other financing costs, net(1)	13,242		(62)		5,416		(2,141)		38,379		—		54,834
Derivatives, net	—		—		—		—		(21,566)		—		(21,566)
Other expenses, net	(11,084)		(6,842)		433		1,915		493		21,566		6,481
Total costs and expenses	144,067		60,779		92,361		111,719		62,414		(14,062)		457,278
Income (loss) before income taxes	60,885		3,811		(72,122)		(7,800)		(48,534)		—		(63,760)
Income tax expense (benefit)	21,993		1,493		—		97		397		—		23,980
Net income (loss)	$	38,892	$	2,318	$	(72,122)	$	(7,897)	$	(48,931)	$	—	$	(87,740)

Consolidated capital expenditures, net	$	37,738	$	3,914	$	13,105	$	31,181	$	169	$	—	$	86,107


	Ghana		Equatorial Guinea(2)		Mauritania/Senegal		Gulf of America		Corporate & Other		Eliminations		Total
	(In thousands)
Six months ended June 30, 2025
Revenues and other income:
Oil and gas revenue	$	355,959	$	98,997	$	22,936	$	204,878	$	—	$	—	$	682,770
Gain on sale of assets	—		—		—		600		—		—		600
Other income, net	498		—		—		708		60,671		(61,298)		579
Total revenues and other income	356,457		98,997		22,936		206,186		60,671		(61,298)		683,949
Costs and expenses:
Oil and gas production	136,668		56,935		127,242		89,581		—		—		410,426
Exploration expenses	70		1,469		3,737		7,145		1,317		—		13,738
General and administrative	6,189		2,970		5,103		8,453		98,746		(76,132)		45,329
Depletion, depreciation and amortization	88,440		42,568		15,595		125,039		293		—		271,935

Interest and other financing costs, net(1)	24,384		(129)		4,402		(4,161)		82,180		—		106,676
Derivatives, net	—		—		—		—		(14,834)		—		(14,834)
Other expenses, net	(5,888)		(5,317)		1,147		3,262		432		14,834		8,470
Total costs and expenses	249,863		98,496		157,226		229,319		168,134		(61,298)		841,740
Income (loss) before income taxes	106,594		501		(134,290)		(23,133)		(107,463)		—		(157,791)
Income tax expense (benefit)	38,669		892		—		(14)		1,008		—		40,555
Net income (loss)	$	67,925	$	(391)	$	(134,290)	$	(23,119)	$	(108,471)	$	—	$	(198,346)

Consolidated capital expenditures, net	$	56,696	$	2,557	$	62,118	$	49,513	$	1,411	$	—	$	172,295

As of June 30, 2025
Property and equipment, net	$	961,336	$	446,405	$	2,106,488	$	827,437	$	16,146	$	—	$	4,357,812
Total assets	$	3,644,403	$	2,458,795	$	3,352,428	$	4,112,600	$	25,932,829	$	(34,288,049)	$	5,213,006

______________________________________

(1)Interest expense is recorded based on actual third-party and intercompany debt agreements. Capitalized interest is recorded on the business unit where the assets reside.

(2)In June 2026, the Company completed the disposition of its interests in the Ceiba Field and Okume Complex production assets located in Block G offshore Equatorial Guinea. The disposition did not qualify for discontinued operations presentation. See Note 3 - Acquisitions and Divestitures for additional information.


	Six Months Ended June 30,
	2026		2025
	(In thousands)
Consolidated capital expenditures:
Consolidated Statements of Cash Flows - Investing activities:
Oil and gas assets	$	163,477	$	172,766


Consolidated Statement of Cash Flows - Financing activities:
Financing lease	14,951		—
Adjustments:
Changes in capital accruals	5,473		(5,910)
Exploration expense, excluding unsuccessful well costs and leasehold impairments(1)	8,982		13,577
Capitalized interest	(4,096)		(8,510)
Other	7,745		372
Total consolidated capital expenditures, net	$	196,532	$	172,295

______________________________________

(1)Costs related to unsuccessful exploratory wells and leaseholds that are subsequently written off to Exploration expense are included in oil and gas assets when incurred.

- Definition

Tabular disclosure of segment reporting. Includes, but is not limited to, reconciliation of reportable segment amount to corresponding consolidated total.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-31

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-34

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-30

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26C

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26B

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
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-Name Accounting Standards Codification
-Section 50
-Paragraph 26A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26A

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
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-Name Accounting Standards Codification
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-Paragraph 25
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-25

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-15

+ Details

Derivative Financial Instruments - Schedule of Derivative Instruments and Gain/(Loss) from Derivatives (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Derivative instruments, Balance Sheet Location
Derivatives assets—current	$ 459	$ 47,816
Derivatives assets—long-term	2,335	2,681
Derivatives liabilities—current	(11,633)	0
Derivatives liabilities—long-term	(5,129)	0
Derivatives not designated as hedging instruments
Derivative instruments, Balance Sheet Location
Total derivatives not designated as hedging instruments	(13,111)	50,497
Derivatives not designated as hedging instruments \| Commodity
Derivative instruments, Balance Sheet Location
Derivatives assets—current	459	47,816
Derivatives assets—long-term	2,335	2,681
Derivatives liabilities—current	(11,633)	0
Derivatives liabilities—long-term	(5,129)	0
Derivatives not designated as hedging instruments \| Provisional sales contracts
Derivative instruments, Balance Sheet Location
Derivatives assets—current	$ 857	$ 0

Property and Equipment - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Feb. 28, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Property, Plant, and Equipment [Line Items]
Depletion expense		$ 111,800	$ 141,700	$ 223,500	$ 253,100
Proved properties		7,763,259		7,763,259		$ 8,301,679
TEN FPSO
Property, Plant, and Equipment [Line Items]
Gross purchase price	$ 205,000
Proved properties		$ 88,200		$ 88,200

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 905
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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-URI https://asc.fasb.org/1943274/2147482338/360-10-05-3

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-Publisher FASB
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Reference 7: http://www.xbrl.org/2003/role/exampleRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 360
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-Name Accounting Standards Codification
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-Paragraph 1
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Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 40
-Name Accounting Standards Codification
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-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482558/350-40-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
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-Section 50
-Paragraph 7A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A

+ Details

Fair Value Measurements

6 Months Ended

Jun. 30, 2026

Fair Value Disclosures [Abstract]

Fair Value Measurements

•Level 1 — quoted prices for identical assets or liabilities in active markets.

The following tables present the Company’s assets and liabilities that are measured at fair value on a recurring basis as of June 30, 2026 and December 31, 2025, for each fair value hierarchy level:


	Fair Value Measurements Using:
	Quoted Prices in
	Active Markets for		Significant Other		Significant
	Identical Assets		Observable Inputs		Unobservable Inputs
	(Level 1)		(Level 2)		(Level 3)		Total
	(In thousands)
June 30, 2026
Assets:
Commodity derivatives	$	—	$	2,794	$	—	$	2,794
Provisional sales contracts	—		857		—		857

Debt securities held in decommissioning trust fund	—		35,652		$	—	35,652
Liabilities:
Commodity derivatives	—		(16,762)		—		(16,762)


Total	$	—	$	22,541	$	—	$	22,541
December 31, 2025
Assets:
Commodity derivatives	$	—	$	50,497	$	—	$	50,497


Debt securities held in decommissioning trust fund	—		23,707		—		23,707




Total	$	—	$	74,204	$	—	$	74,204

The book values of cash and cash equivalents and restricted cash approximate fair value based on Level 1 inputs. Joint interest billings, oil and gas sales and other receivables, and accounts payable and accrued liabilities approximate fair value due to the short-term nature of these instruments. Our long-term receivables, after any allowances for credit losses, and other long-term assets approximate fair value. The estimates of fair value of these items are based on Level 2 inputs.

Commodity Derivatives

Our commodity derivatives represent swaps, crude oil collars, put options and call options for notional barrels of oil at fixed Dated Brent and NYMEX WTI oil prices. The values attributable to our oil derivatives are based on (i) the contracted notional volumes, (ii) independent active futures price quotes for the respective index, (iii) a credit-adjusted yield curve applicable to each counterparty by reference to the credit default swap (“CDS”) market and (iv) an independently sourced estimate of volatility for the respective index. The volatility estimate was provided by certain independent brokers who are active in buying and selling oil options and was corroborated by market-quoted volatility factors. The deferred premium is included in the fair market value of the commodity derivatives. See Note 9 — Derivative Financial Instruments for additional information regarding the Company’s derivative instruments.

Provisional Sales Contracts

The value attributable to provisional sales contracts derivative is based on (i) the sales volumes and (ii) the difference in the independent active futures price quotes for the respective index over the term of the pricing period designated in the sales contract and the spot price on the date of sale.

Decommissioning Trust Fund

In April 2024, a decommissioning trust agreement with the Jubilee unit partners to cash fund future retirement costs associated with the Jubilee Field was finalized. Each partner contributes annually to the trust in proportion to its respective paying interest of the estimated future dismantlement, abandonment and restoration costs associated with the decommissioning of the Jubilee Field. Contributions to the trust are used by the trustee of the fund, the Bank of Ghana, to purchase and sell authorized securities at the direction of the Jubilee unit partners.

As of June 30, 2026, the investments held in the decommissioning trust fund are US Treasury debt securities. We have classified the investments as trading securities and recorded such investments at fair market value as a long-term investment in our consolidated balance sheet using observable inputs including Kosmos’ share of the fund and broker/dealer bid/ask prices of the investments held by the fund at June 30, 2026. Contributions made to the decommissioning trust are reported as investing activities in our consolidated cash flows. All realized and unrealized gains and losses resulting from the sales and maturities or changes in fair value of the securities are recognized in Other income, net. During the six months ended June 30, 2026 and 2025, we contributed $11.6 million and $11.5 million to the decommissioning trust fund, respectively.

The following table summarizes the cost and fair value, purchases, proceeds from the sale and maturities, and the unrealized gains (losses) for Kosmos’ portion of the investments in debt securities held by the decommissioning trust during the six months ended June 30, 2026 and 2025:


	Three Months Ended June 30,						Six Months Ended June 30,
Type of Security	Purchases		Net Proceeds (1)		Unrealized Gain (Loss)		Purchases		Net Proceeds (1)		Unrealized Gain (Loss)
	(In thousands)
2026
Debt securities	$	209	$	—	$	(18)	$	12,051	$	—	$	(106)
Cash and cash equivalents	—		(7)		—		—		1		—
Other(1)	—		156		—		—		181		—
Total	$	209	$	149	$	(18)	$	12,051	$	182	$	(106)
2025
Debt securities	$	198	$	—	$	22	$	12,406	$	—	$	131
Cash and cash equivalents	—		2		—		—		(745)		—
Other(1)	—		23		—		—		166		—
Total	$	198	$	25	$	22	$	12,406	$	(579)	$	131

(1) Represents net receivables relating to interest.

The following table presents the costs and fair values of investments in debt securities held in the decommissioning trust fund according to the contractual maturities at June 30, 2026 and December 31, 2025:


	June 30, 2026				December 31, 2025
	Cost		Estimated Fair Value		Cost		Estimated Fair Value
	(In thousands)
Less than 5 years	$	35,616	$	35,652	$	23,565	$	23,707
5 years to 10 years	—		—		—		—
Due after 10 years	—		—		—		—
Total	$	35,616	$	35,652	$	23,565	$	23,707

Debt

The following table presents the carrying values and fair values at June 30, 2026 and December 31, 2025:


	June 30, 2026				December 31, 2025
	Carrying Value		Fair Value		Carrying Value		Fair Value
	(In thousands)
7.125% Senior Notes	$	—	$	—	$	99,942	$	99,303
7.750% Senior Notes	99,747		99,456		348,757		321,394
7.500% Senior Notes	398,825		381,313		398,426		270,125
8.750% Senior Notes	495,866		409,555		495,564		283,575
3.125% Convertible Senior Notes	393,864		293,572		393,097		172,704
11.250% Senior Secured Bonds	350,000		359,482		—		—
GoA Term Loan Facility	196,429		196,429		150,000		150,000
Facility	773,000		773,000		1,200,000		1,200,000
Total	$	2,707,731	$	2,512,807	$	3,085,786	$	2,497,101

The carrying values of our 7.125% Senior Notes, 7.750% Senior Notes, 7.500% Senior Notes, 8.750% Senior Notes and 3.125% Convertible Senior Notes represent the principal amounts outstanding less unamortized discounts. The fair values of our 7.125% Senior Notes, 7.750% Senior Notes, 7.500% Senior Notes, 8.750% Senior Notes, 3.125% Convertible Senior Notes and 11.250% Senior Secured Bonds are based on quoted market prices, which results in a Level 1 fair value measurement. The carrying value of the GoA Term Loan Facility and Facility approximates fair value since they are subject to short-term floating interest rates that approximate the rates available to us for those periods.

Nonrecurring Fair Value Measurements - Long-lived assets

Certain long-lived assets are reported at fair value on a non-recurring basis on the Company's consolidated balance sheet. These long-lived assets are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances. Our long-lived assets are reviewed for impairment when changes in circumstances indicate that the carrying amount of an asset may not be recoverable.

The Company calculates the estimated fair values of its long-lived assets using the income approach described in the ASC 820 — Fair Value Measurements. Significant inputs associated with the calculation of estimated discounted future net cash flows include anticipated future production, pricing estimates, capital and operating costs, market-based weighted average cost of capital, and risk adjustment factors applied to reserves. These are classified as Level 3 fair value assumptions. The Company utilizes an average of third-party industry forecasts of Dated Brent, adjusted for location and quality differentials, to determine our pricing assumptions. In order to evaluate the sensitivity of the assumptions, we analyze sensitivities to prices, production, and risk adjustment factors.

During the three and six months ended June 30, 2026 and 2025, the Company did not recognize impairment of proved oil and gas properties. If we experience material declines in oil pricing expectations in the future, significant increases in our estimated future expenditures or a significant decrease in our estimated production profile, our long-lived assets could be at risk of impairment.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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+ Details

Accounting Policies - Schedule of Concentration of Credit Risk (Details) - Revenue Benchmark - Customer Concentration Risk	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
BP plc
Disaggregation of Revenue [Line Items]
Concentration risk, percentage	77.00%	18.00%	62.00%	19.00%
Shell Trading (US) Company
Disaggregation of Revenue [Line Items]
Concentration risk, percentage	18.00%	4.00%	20.00%	5.00%

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References + Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Debt - Schedule of Redemption Price (Details) - 11.250% Senior Secured Bonds - Senior Secured Bond	1 Months Ended
	Jan. 31, 2026
Debt Instrument [Line Items]
Redemption price percentage (as a percent)	100.00%
Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Redemption price percentage (as a percent)	105.625%
Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Redemption price percentage (as a percent)	103.375%
Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Redemption price percentage (as a percent)	100.00%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Leases - Schedule of Other Information Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Lessee, Lease, Description [Line Items]
Other assets (right-of-use assets)	$ 8,705	$ 10,059
Accrued liabilities (current maturities of leases)	3,060	2,777
Other long-term liabilities (non-current maturities of leases)	7,852	9,438
Property and equipment, net	69,454	0
Accrued liabilities	73,203	0
Proved properties	7,763,259	8,301,679
Accumulated depletion	4,624,781	$ 4,780,826
TEN FPSO
Lessee, Lease, Description [Line Items]
Proved properties	88,200
Accumulated depletion	$ 18,700

Debt - Senior Notes, Capped Call Transaction and GoA Term Loan Facility (Details)					1 Months Ended							3 Months Ended	4 Months Ended	6 Months Ended
	Mar. 24, 2026 USD ($)	Oct. 01, 2025 USD ($)	Sep. 24, 2025 USD ($) tranche	Sep. 24, 2024 USD ($)	Jan. 31, 2026 USD ($)	Oct. 31, 2025 USD ($)	Sep. 30, 2024 USD ($)	Mar. 31, 2024 USD ($) $ / shares	Oct. 31, 2021 USD ($)	Mar. 31, 2021 USD ($)	Apr. 30, 2019 USD ($)	Mar. 31, 2026 USD ($)	Jan. 31, 2026 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Repayments of senior notes														$ 347,184,000	$ 0
7.125% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)											7.125%
Debt, face amount											$ 650,000,000.0
Proceeds from debt, net of issuance costs											$ 640,000,000.0
Repayments of senior notes				$ 400,000,000.0	$ 100,000,000.0	$ 150,000,000.0							$ 250,000,000.0
7.750% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)									7.75%
Debt, face amount									$ 400,000,000.0
Proceeds from debt, net of issuance costs									$ 395,000,000.0
Repayments of senior notes				50,000,000.0								$ 249,800,000		$ 250,000,000.0
7.500% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)										7.50%
Debt, face amount										$ 450,000,000.0
Proceeds from debt, net of issuance costs										$ 444,400,000
Repayments of senior notes				$ 49,700,000
8.750% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)							8.75%
Debt, face amount							$ 500,000,000.0
Proceeds from debt, net of issuance costs							$ 494,900,000
3.125% Convertible Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)								3.125%						3.125%		3.125%	3.125%
Debt, face amount								$ 400,000,000.0
Proceeds from debt, net of issuance costs								390,400,000
Unamortized deferred financing costs								$ 9,600,000
Debt instrument, interest rate (as a percent)														3.70%
Debt instrument, conversion price (in dollars per share) \| $ / shares								$ 7.02
Payments for capped call transactions, financing activities								$ 49,800,000
3.125% Convertible Senior Notes \| Secured Debt
Debt Instrument [Line Items]
Debt instrument, conversion ratio								0.1424501
GoA Term Loan Facility \| Secured Debt
Debt Instrument [Line Items]
Number of tranches \| tranche			2
Repayment of debt	$ 53,600,000
Applicable margin (as a percent)			3.75%
Life coverage ratio			1.50
Net leverage ratio			3.50
GoA Term Loan Facility, Tranche One \| Secured Debt
Debt Instrument [Line Items]
Debt, face amount			$ 150,000,000.0
Proceeds from debt, net of issuance costs		$ 147,200,000
Debt term (in years)			4 years
GoA Term Loan Facility, Tranche Two \| Secured Debt
Debt Instrument [Line Items]
Debt, face amount			$ 100,000,000.0
Proceeds from debt, net of issuance costs					$ 98,500,000

Suspended Well Costs - Narrative (Details)	Jul. 31, 2026
Tiberius \| Keathley Canyon Blocks 964 Offshore Gulf Of America \| Subsequent Event
Capitalized Contract Cost [Line Items]
Participation interest (as a percent)	33.34%

Derivative Financial Instruments

6 Months Ended

Jun. 30, 2026

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Derivative Financial Instruments

We use financial derivative contracts to manage exposures to commodity price and interest rate fluctuations. We do not hold or issue derivative financial instruments for trading purposes.

We manage market and counterparty credit risk in accordance with our policies and guidelines. In accordance with these policies and guidelines, our management determines the appropriate timing and extent of derivative transactions. We have included an estimate of non-performance risk in the fair value measurement of our derivative contracts as required by ASC 820 — Fair Value Measurement.

Oil Derivative Contracts

The following table sets forth the volumes in barrels underlying the Company’s outstanding oil derivative contracts and the weighted average prices per Bbl for those contracts as of June 30, 2026. Volumes and weighted average prices are net of any offsetting derivative contracts entered into.


				Weighted Average Price per Bbl
				Net Deferred
				Premium
				Payable/		Sold
Term	Type of Contract	Index	MBbl	(Receivable)	Swap	Put	Floor	Ceiling
2026:
Jul - Dec	Three-way collars	Dated Brent	1,000	—	—	50.00	60.00	75.51
Jul - Dec	Swaps(1)	Dated Brent	500	—	72.46	—	—	100.00
Jul - Dec	Swaps(1)	Dated Brent	1,000	—	69.70	55.00	—	—
Jul - Dec	Swaps(1)	NYMEX WTI	750	—	64.83	50.00	—	—
2027:
Jan - Dec	Three-way collars	Dated Brent	2,000	0.40	—	47.50	60.00	75.00
Jan - Jun	Three-way collars	Dated Brent	2,000	0.03	—	55.00	70.00	85.00
Jan - Dec	Three-way collars	NYMEX WTI	1,000	0.50	—	55.00	70.00	90.00

__________________________________

(1)Includes option contracts sold to counterparties to enhance Swaps.

In July 2026, we entered into Dated Brent two-way collar contracts for 2.0 MMBbl from January 2027 through December 2027 with a weighted average floor price of $67.50 per barrel and a ceiling price of $90.00 per barrel.

The following tables disclose the Company’s derivative instruments as of June 30, 2026 and December 31, 2025, and gain/(loss) from derivatives during the three and six months ended June 30, 2026 and 2025, respectively:


		Estimated Fair Value
		Asset (Liability)
Type of Contract	Balance Sheet Location	June 30, 2026		December 31, 2025
		(In thousands)
Derivatives not designated as hedging instruments:
Derivative assets:
Commodity	Derivatives assets—current	$	459	$	47,816
Provisional sales contracts	Receivables: Oil and gas sales	857		—

Commodity	Derivatives assets—long-term	2,335		2,681
Derivative liabilities:
Commodity	Derivatives liabilities—current	(11,633)		—


Commodity	Derivatives liabilities—long-term	(5,129)		—

Total derivatives not designated as hedging instruments		$	(13,111)	$	50,497


		Amount of Gain/(Loss)				Amount of Gain/(Loss)
		Three Months Ended				Six Months Ended
		June 30,				June 30,
Type of Contract	Location of Gain/(Loss)	2026		2025		2026		2025
		(In thousands)
Derivatives not designated as hedging instruments:
Provisional sales contracts	Oil and gas revenue	$	(11,126)	$	(6,780)	$	(62,105)	$	(7,607)
Commodity	Derivatives, net	51,809		21,566		(200,187)		14,834
Interest rate	Interest expense	—		683		—		656
Total derivatives not designated as hedging instruments		$	40,683	$	15,469	$	(262,292)	$	7,883

Offsetting of Derivative Assets and Derivative Liabilities

Our derivative instruments which are subject to master netting arrangements with our counterparties only have the right of offset when there is an event of default. As of June 30, 2026 and December 31, 2025, there was not an event of default and, therefore, the associated gross asset or gross liability amounts related to these arrangements are presented on the consolidated balance sheets.

- Definition

The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.

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+ Details

Cover - shares	6 Months Ended
Cover - shares	Jun. 30, 2026	Jul. 30, 2026
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2026
Document Transition Report	false
Entity File Number	001-35167
Entity Registrant Name	Kosmos Energy Ltd.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	98-0686001
Entity Address, Address Line One	8176 Park Lane
Entity Address, City or Town	Dallas,
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75231
Title of 12(b) Security	Common Stock $0.01 par value
Trading Symbol	KOS
Security Exchange Name	NYSE
City Area Code	214
Local Phone Number	445 9600
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		595,487,651
Entity Central Index Key	0001509991
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q2

Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025
Oil and gas properties:
Proved properties	$ 7,763,259	$ 8,301,679
Unproved properties	210,786	210,161
Total oil and gas properties	7,974,045	8,511,840
Accumulated depletion	(4,624,781)	(4,780,826)
Oil and gas properties, net	3,349,264	3,731,014
Other property	69,046	68,255
Accumulated depreciation	(66,784)	(65,485)
Other property, net	2,262	2,770
Property and equipment, net	$ 3,351,526	$ 3,733,784	$ 4,357,812

Income Taxes

6 Months Ended

Jun. 30, 2026

Income Tax Disclosure [Abstract]

Income Taxes

We evaluate our estimated annual effective income tax rate each quarter, based on current and forecasted business results and enacted tax laws, and apply this tax rate to our ordinary income or loss to calculate our estimated tax expense or benefit. The Company excludes zero statutory tax rate and tax-exempt jurisdictions from our evaluation of the estimated annual effective income tax rate. The tax effect of discrete items are recognized in the period in which they occur at the applicable statutory tax rate.

Income (loss) before income taxes is composed of the following:


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
	(In thousands)
United States	$	14,647	$	(43,691)	$	(36,949)	$	(104,461)
Foreign (1)	267,826		(20,069)		78,335		(53,330)
Income (loss) before income taxes	$	282,473	$	(63,760)	$	41,386	$	(157,791)

For the three months ended March 31, 2026 and 2025, our effective tax rate was 35% and (38)%, respectively. For the six months ended June 30, 2026 and 2025, our effective tax rate was 199% and (26)%, respectively. For the three and six months ended June 30, 2026 and 2025, our overall effective tax rate was impacted by:

•The difference in our 21% U.S. income tax reporting rate and the statutory income tax rates applicable to our foreign operations, primarily in Ghana.

•Jurisdictions that have a 0% statutory tax rate or that are exempt,

•Jurisdictions where we have incurred losses and have recorded valuation allowances against the corresponding deferred tax assets, and

•Other non-deductible expenses

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 740
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
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-URI https://asc.fasb.org/1943274/2147477617/942-740-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Paragraph 1
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-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 5: http://www.xbrl.org/2003/role/exampleRef
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-Name Accounting Standards Codification
-Section 55
-Paragraph 231
-Publisher FASB
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Paragraph 12C
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/740/tableOfContent

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147482603/740-30-50-2

+ Details

Business Segment Information - Schedule of Business Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2026	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Segment Reporting [Line Items]
Oil and gas revenue	$ 607,253		$ 392,635		$ 977,981	$ 682,770
Gain on sale of assets	9,421		600		9,421	600
Other income, net	361		283		530	579
Total revenues and other income	617,035		393,518		987,932	683,949
Oil and gas production	179,429		243,118		310,024	410,426
Exploration expenses	3,197		4,069		22,941	13,738
General and administrative	19,263		19,074		46,973	45,329
Depletion, depreciation and amortization	120,501		151,268		240,374	271,935
Interest and other financing costs, net	53,700		54,834		112,502	106,676
Derivatives, net	(51,809)		(21,566)		200,187	(14,834)
Other expenses, net	10,281		6,481		13,545	8,470
Total costs and expenses	334,562		457,278		946,546	841,740
Income (loss) before income taxes	282,473		(63,760)		41,386	(157,791)
Income tax expense (benefit)	97,698		23,980		82,185	40,555
Net income (loss)	184,775	$ (225,574)	(87,740)	$ (110,606)	(40,799)	(198,346)
Consolidated capital expenditures, net	105,052		86,107		196,532	172,295
Property and equipment, net	3,351,526		4,357,812		3,351,526	4,357,812	$ 3,733,784
Total assets	4,310,147		5,213,006		4,310,147	5,213,006	$ 4,696,626
Operating Segments \| Ghana
Segment Reporting [Line Items]
Oil and gas revenue	356,595		204,706		557,859	355,959
Gain on sale of assets	0		0		0	0
Other income, net	361		246		530	498
Total revenues and other income	356,956		204,952		558,389	356,457
Oil and gas production	59,031		95,357		87,455	136,668
Exploration expenses	(3)		24		0	70
General and administrative	3,227		2,904		7,167	6,189
Depletion, depreciation and amortization	54,075		43,624		107,592	88,440
Interest and other financing costs, net	10,803		13,242		22,566	24,384
Derivatives, net	0		0		0	0
Other expenses, net	(21,970)		(11,084)		132,978	(5,888)
Total costs and expenses	105,163		144,067		357,758	249,863
Income (loss) before income taxes	251,793		60,885		200,631	106,594
Income tax expense (benefit)	91,498		21,993		73,950	38,669
Net income (loss)	160,295		38,892		126,681	67,925
Consolidated capital expenditures, net	70,494		37,738		140,105	56,696
Property and equipment, net	1,001,641		961,336		1,001,641	961,336
Total assets	3,429,540		3,644,403		3,429,540	3,644,403
Operating Segments \| Equatorial Guinea
Segment Reporting [Line Items]
Oil and gas revenue	47,161		64,590		69,556	98,997
Gain on sale of assets	9,421		0		9,421	0
Other income, net	0		0		0	0
Total revenues and other income	56,582		64,590		78,977	98,997
Oil and gas production	25,244		39,957		40,097	56,935
Exploration expenses	146		(892)		1,260	1,469
General and administrative	1,003		1,150		2,468	2,970
Depletion, depreciation and amortization	2,611		27,468		6,732	42,568
Interest and other financing costs, net	(22)		(62)		(57)	(129)
Derivatives, net	0		0		0	0
Other expenses, net	(226)		(6,842)		67,842	(5,317)
Total costs and expenses	28,756		60,779		118,342	98,496
Income (loss) before income taxes	27,826		3,811		(39,365)	501
Income tax expense (benefit)	5,093		1,493		5,743	892
Net income (loss)	22,733		2,318		(45,108)	(391)
Consolidated capital expenditures, net	2,090		3,914		2,599	2,557
Property and equipment, net	13,999		446,405		13,999	446,405
Total assets	132,939		2,458,795		132,939	2,458,795
Operating Segments \| Mauritania/Senegal
Segment Reporting [Line Items]
Oil and gas revenue	92,058		20,239		144,325	22,936
Gain on sale of assets	0		0		0	0
Other income, net	0		0		0	0
Total revenues and other income	92,058		20,239		144,325	22,936
Oil and gas production	65,827		69,141		121,168	127,242
Exploration expenses	238		2,119		574	3,737
General and administrative	2,710		2,575		5,420	5,103
Depletion, depreciation and amortization	35,221		12,677		66,017	15,595
Interest and other financing costs, net	8,379		5,416		13,960	4,402
Derivatives, net	0		0		0	0
Other expenses, net	1,352		433		2,077	1,147
Total costs and expenses	113,727		92,361		209,216	157,226
Income (loss) before income taxes	(21,669)		(72,122)		(64,891)	(134,290)
Income tax expense (benefit)	9		0		9	0
Net income (loss)	(21,678)		(72,122)		(64,900)	(134,290)
Consolidated capital expenditures, net	3,216		13,105		5,266	62,118
Property and equipment, net	1,846,885		2,106,488		1,846,885	2,106,488
Total assets	6,326,648		3,352,428		6,326,648	3,352,428
Operating Segments \| Gulf of America
Segment Reporting [Line Items]
Oil and gas revenue	111,439		103,100		206,241	204,878
Gain on sale of assets	0		600		0	600
Other income, net	46		219		103	708
Total revenues and other income	111,485		103,919		206,344	206,186
Oil and gas production	29,327		38,663		61,304	89,581
Exploration expenses	2,653		2,649		6,667	7,145
General and administrative	4,886		3,269		10,690	8,453
Depletion, depreciation and amortization	27,740		67,364		59,026	125,039
Interest and other financing costs, net	1,320		(2,141)		3,694	(4,161)
Derivatives, net	0		0		0	0
Other expenses, net	(4,662)		1,915		25,829	3,262
Total costs and expenses	61,264		111,719		167,210	229,319
Income (loss) before income taxes	50,221		(7,800)		39,134	(23,133)
Income tax expense (benefit)	70		97		71	(14)
Net income (loss)	50,151		(7,897)		39,063	(23,119)
Consolidated capital expenditures, net	28,382		31,181		46,907	49,513
Property and equipment, net	487,042		827,437		487,042	827,437
Total assets	3,884,596		4,112,600		3,884,596	4,112,600
Corporate & Other
Segment Reporting [Line Items]
Oil and gas revenue	0		0		0	0
Gain on sale of assets	0		0		0	0
Other income, net	131		13,880		291,492	60,671
Total revenues and other income	131		13,880		291,492	60,671
Oil and gas production	0		0		0	0
Exploration expenses	163		169		14,440	1,317
General and administrative	41,984		44,804		95,198	98,746
Depletion, depreciation and amortization	854		135		1,007	293
Interest and other financing costs, net	33,220		38,379		72,339	82,180
Derivatives, net	(51,809)		(21,566)		200,187	(14,834)
Other expenses, net	1,417		493		2,444	432
Total costs and expenses	25,829		62,414		385,615	168,134
Income (loss) before income taxes	(25,698)		(48,534)		(94,123)	(107,463)
Income tax expense (benefit)	1,028		397		2,412	1,008
Net income (loss)	(26,726)		(48,931)		(96,535)	(108,471)
Consolidated capital expenditures, net	870		169		1,655	1,411
Property and equipment, net	1,959		16,146		1,959	16,146
Total assets	29,688,971		25,932,829		29,688,971	25,932,829
Eliminations
Segment Reporting [Line Items]
Oil and gas revenue	0		0		0	0
Gain on sale of assets	0		0		0	0
Other income, net	(177)		(14,062)		(291,595)	(61,298)
Total revenues and other income	(177)		(14,062)		(291,595)	(61,298)
Oil and gas production	0		0		0	0
Exploration expenses	0		0		0	0
General and administrative	(34,547)		(35,628)		(73,970)	(76,132)
Depletion, depreciation and amortization	0		0		0	0
Interest and other financing costs, net	0		0		0	0
Derivatives, net	0		0		0	0
Other expenses, net	34,370		21,566		(217,625)	14,834
Total costs and expenses	(177)		(14,062)		(291,595)	(61,298)
Income (loss) before income taxes	0		0		0	0
Income tax expense (benefit)	0		0		0	0
Net income (loss)	0		0		0	0
Consolidated capital expenditures, net	0		0		0	0
Property and equipment, net	0		0		0	0
Total assets	$ (39,152,547)		$ (34,288,049)		$ (39,152,547)	$ (34,288,049)

Suspended Well Costs - Schedule of Suspended Well Costs (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2026 USD ($) project	Dec. 31, 2025 USD ($) project
Reconciliation of capitalized exploratory well costs on completed wells
Beginning balance	$ 73,141
Additions to capitalized exploratory well costs pending the determination of proved reserves	4,985
Reclassification due to determination of proved reserves	0
Capitalized exploratory well costs charged to expense	0
Ending balance	78,126
Aging of capitalized exploratory well costs and number of projects for which exploratory well costs were capitalized for more than one year
Exploratory well costs capitalized for a period of one year or less	0	$ 0
Exploratory well costs capitalized for a period of one to five years	78,126	73,141
Exploratory well costs capitalized for a period of six to ten years	0	0
Ending balance	$ 78,126	$ 73,141
Number of projects that have exploratory well costs that have been capitalized for a period greater than one year \| project	1	1

Business Segment Information

6 Months Ended

Jun. 30, 2026

Segment Reporting [Abstract]

Business Segment Information

Kosmos is engaged in a single line of business, which is the exploration, development and production of oil and gas. For the three and six months ended June 30, 2026, the Company’s segment information is presented for four geographic reporting segments: Ghana, Equatorial Guinea, Mauritania/Senegal and the Gulf of America. The Equatorial Guinea segment reflects the results of the Ceiba Field and Okume Complex production assets located in Block G offshore Equatorial Guinea through the date of sale in June 2026. See Note 3 - Acquisitions and Divestitures for additional information. The Company’s Chief Operating Decision Maker (“CODM”) is the Chief Executive Officer, who makes decisions about allocating resources and assessing performance for the entire company. To assess performance of the reporting segments, the CODM regularly reviews oil and gas revenues, oil and gas production costs, exploration expenses and capital expenditures by reporting segment in deciding how to allocate resources and in assessing performance. Capital expenditures, as defined by the Company, may not be comparable to similarly titled measures used by other companies and should be considered in conjunction with our consolidated financial statements and notes thereto. Financial information for each area is presented below:


	Ghana		Equatorial Guinea(2)		Mauritania/Senegal		Gulf of America		Corporate & Other		Eliminations		Total
	(In thousands)
Three Months Ended June 30, 2026
Revenues and other income:
Oil and gas revenue	$	356,595	$	47,161	$	92,058	$	111,439	$	—	$	—	$	607,253
Gain on sale of assets	—		9,421		—		—		—		—		9,421
Other income, net	361		—		—		46		131		(177)		361
Total revenues and other income	356,956		56,582		92,058		111,485		131		(177)		617,035
Costs and expenses:
Oil and gas production	59,031		25,244		65,827		29,327		—		—		179,429
Exploration expenses	(3)		146		238		2,653		163		—		3,197
General and administrative	3,227		1,003		2,710		4,886		41,984		(34,547)		19,263
Depletion, depreciation and amortization	54,075		2,611		35,221		27,740		854		—		120,501

Interest and other financing costs, net(1)	10,803		(22)		8,379		1,320		33,220		—		53,700
Derivatives, net	—		—		—		—		(51,809)		—		(51,809)
Other expenses, net	(21,970)		(226)		1,352		(4,662)		1,417		34,370		10,281
Total costs and expenses	105,163		28,756		113,727		61,264		25,829		(177)		334,562
Income (loss) before income taxes	251,793		27,826		(21,669)		50,221		(25,698)		—		282,473
Income tax expense	91,498		5,093		9		70		1,028		—		97,698
Net income (loss)	$	160,295	$	22,733	$	(21,678)	$	50,151	$	(26,726)	$	—	$	184,775

Consolidated capital expenditures	$	70,494	$	2,090	$	3,216	$	28,382	$	870	$	—	$	105,052


	Ghana		Equatorial Guinea(2)		Mauritania/Senegal		Gulf of America		Corporate & Other		Eliminations		Total
	(In thousands)
Six months ended June 30, 2026
Revenues and other income:
Oil and gas revenue	$	557,859	$	69,556	$	144,325	$	206,241	$	—	$	—	$	977,981
Gain on sale of assets	—		9,421		—		—		—		—		9,421
Other income, net	530		—		—		103		291,492		(291,595)		530
Total revenues and other income	558,389		78,977		144,325		206,344		291,492		(291,595)		987,932
Costs and expenses:
Oil and gas production	87,455		40,097		121,168		61,304		—		—		310,024
Exploration expenses	—		1,260		574		6,667		14,440		—		22,941
General and administrative	7,167		2,468		5,420		10,690		95,198		(73,970)		46,973
Depletion, depreciation and amortization	107,592		6,732		66,017		59,026		1,007		—		240,374

Interest and other financing costs, net(1)	22,566		(57)		13,960		3,694		72,339		—		112,502
Derivatives, net	—		—		—		—		200,187		—		200,187
Other expenses, net	132,978		67,842		2,077		25,829		2,444		(217,625)		13,545
Total costs and expenses	357,758		118,342		209,216		167,210		385,615		(291,595)		946,546
Income (loss) before income taxes	200,631		(39,365)		(64,891)		39,134		(94,123)		—		41,386
Income tax expense (benefit)	73,950		5,743		9		71		2,412		—		82,185
Net income (loss)	$	126,681	$	(45,108)	$	(64,900)	$	39,063	$	(96,535)	$	—	$	(40,799)

Consolidated capital expenditures, net	$	140,105	$	2,599	$	5,266	$	46,907	$	1,655	$	—	$	196,532

As of June 30, 2026
Property and equipment, net	$	1,001,641	$	13,999	$	1,846,885	$	487,042	$	1,959	$	—	$	3,351,526
Total assets	$	3,429,540	$	132,939	$	6,326,648	$	3,884,596	$	29,688,971	$	(39,152,547)	$	4,310,147

______________________________________

(1)Interest expense is recorded based on actual third-party and intercompany debt agreements. Capitalized interest is recorded on the business unit where the assets reside.


	Ghana		Equatorial Guinea(2)		Mauritania/Senegal		Gulf of America		Corporate & Other		Eliminations		Total
	(In thousands)
Three months ended June 30, 2025
Revenues and other income:
Oil and gas revenue	$	204,706	$	64,590	$	20,239	$	103,100	$	—	$	—	$	392,635
Gain on sale of assets	—		—		—		600		—		—		600
Other income, net	246		—		—		219		13,880		(14,062)		283
Total revenues and other income	204,952		64,590		20,239		103,919		13,880		(14,062)		393,518
Costs and expenses:
Oil and gas production	95,357		39,957		69,141		38,663		—		—		243,118
Exploration expenses	24		(892)		2,119		2,649		169		—		4,069
General and administrative	2,904		1,150		2,575		3,269		44,804		(35,628)		19,074
Depletion, depreciation and amortization	43,624		27,468		12,677		67,364		135		—		151,268

Interest and other financing costs, net(1)	13,242		(62)		5,416		(2,141)		38,379		—		54,834
Derivatives, net	—		—		—		—		(21,566)		—		(21,566)
Other expenses, net	(11,084)		(6,842)		433		1,915		493		21,566		6,481
Total costs and expenses	144,067		60,779		92,361		111,719		62,414		(14,062)		457,278
Income (loss) before income taxes	60,885		3,811		(72,122)		(7,800)		(48,534)		—		(63,760)
Income tax expense (benefit)	21,993		1,493		—		97		397		—		23,980
Net income (loss)	$	38,892	$	2,318	$	(72,122)	$	(7,897)	$	(48,931)	$	—	$	(87,740)

Consolidated capital expenditures, net	$	37,738	$	3,914	$	13,105	$	31,181	$	169	$	—	$	86,107


	Ghana		Equatorial Guinea(2)		Mauritania/Senegal		Gulf of America		Corporate & Other		Eliminations		Total
	(In thousands)
Six months ended June 30, 2025
Revenues and other income:
Oil and gas revenue	$	355,959	$	98,997	$	22,936	$	204,878	$	—	$	—	$	682,770
Gain on sale of assets	—		—		—		600		—		—		600
Other income, net	498		—		—		708		60,671		(61,298)		579
Total revenues and other income	356,457		98,997		22,936		206,186		60,671		(61,298)		683,949
Costs and expenses:
Oil and gas production	136,668		56,935		127,242		89,581		—		—		410,426
Exploration expenses	70		1,469		3,737		7,145		1,317		—		13,738
General and administrative	6,189		2,970		5,103		8,453		98,746		(76,132)		45,329
Depletion, depreciation and amortization	88,440		42,568		15,595		125,039		293		—		271,935

Interest and other financing costs, net(1)	24,384		(129)		4,402		(4,161)		82,180		—		106,676
Derivatives, net	—		—		—		—		(14,834)		—		(14,834)
Other expenses, net	(5,888)		(5,317)		1,147		3,262		432		14,834		8,470
Total costs and expenses	249,863		98,496		157,226		229,319		168,134		(61,298)		841,740
Income (loss) before income taxes	106,594		501		(134,290)		(23,133)		(107,463)		—		(157,791)
Income tax expense (benefit)	38,669		892		—		(14)		1,008		—		40,555
Net income (loss)	$	67,925	$	(391)	$	(134,290)	$	(23,119)	$	(108,471)	$	—	$	(198,346)

Consolidated capital expenditures, net	$	56,696	$	2,557	$	62,118	$	49,513	$	1,411	$	—	$	172,295

As of June 30, 2025
Property and equipment, net	$	961,336	$	446,405	$	2,106,488	$	827,437	$	16,146	$	—	$	4,357,812
Total assets	$	3,644,403	$	2,458,795	$	3,352,428	$	4,112,600	$	25,932,829	$	(34,288,049)	$	5,213,006

______________________________________

(1)Interest expense is recorded based on actual third-party and intercompany debt agreements. Capitalized interest is recorded on the business unit where the assets reside.

(2)In June 2026, the Company completed the disposition of its interests in the Ceiba Field and Okume Complex production assets located in Block G offshore Equatorial Guinea. The disposition did not qualify for discontinued operations presentation. See Note 3 - Acquisitions and Divestitures for additional information.


	Six Months Ended June 30,
	2026		2025
	(In thousands)
Consolidated capital expenditures:
Consolidated Statements of Cash Flows - Investing activities:
Oil and gas assets	$	163,477	$	172,766


Consolidated Statement of Cash Flows - Financing activities:
Financing lease	14,951		—
Adjustments:
Changes in capital accruals	5,473		(5,910)
Exploration expense, excluding unsuccessful well costs and leasehold impairments(1)	8,982		13,577
Capitalized interest	(4,096)		(8,510)
Other	7,745		372
Total consolidated capital expenditures, net	$	196,532	$	172,295

______________________________________

(1)Costs related to unsuccessful exploratory wells and leaseholds that are subsequently written off to Exploration expense are included in oil and gas assets when incurred.

- Definition

The entire disclosure for segment reporting.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-40

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-URI https://asc.fasb.org/1943274/2147482810/280-10-50-42

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (ee)
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Accounting Policies - Narrative (Details) $ in Millions		3 Months Ended	6 Months Ended
Accounting Policies - Narrative (Details) $ in Millions	Mar. 31, 2026 USD ($)	Mar. 31, 2026 USD ($)	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024	Sep. 30, 2024	Apr. 30, 2024	Mar. 31, 2024	Oct. 31, 2021	Mar. 31, 2021
Inventories
Materials and supplies inventory			$ 132.4	$ 144.9
Hydrocarbons inventory			7.5	$ 27.7
Facility
Cash, Cash Equivalents and Restricted Cash
Debt cover ratio	2.50	2.50					2.50
Restricted cash required		$ 23.5
Debt service reserve account	$ 23.5		$ 23.5
Facility Interest or Senior Notes
Cash, Cash Equivalents and Restricted Cash
Period for contractual future interest payments			6 months
7.750% Senior Notes \| Senior Notes
Cash, Cash Equivalents and Restricted Cash
Interest rate (as a percent)									7.75%
7.500% Senior Notes \| Senior Notes
Cash, Cash Equivalents and Restricted Cash
Interest rate (as a percent)										7.50%
8.750% Senior Notes \| Senior Notes
Cash, Cash Equivalents and Restricted Cash
Interest rate (as a percent)						8.75%
3.125% Convertible Senior Notes \| Senior Notes
Cash, Cash Equivalents and Restricted Cash
Interest rate (as a percent)			3.125%	3.125%	3.125%			3.125%

Acquisitions and Divestitures - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Feb. 24, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Business Combination, Consideration Transferred, Equity Interest [Line Items]
Share sale and purchase agreement, participating interest	40.40%
Share sale and purchase agreement, cash consideration	$ 127,000
Share sale and purchase agreement, initial purchase price	180,000
Share sale and purchase agreement, purchase price adjustments	53,000
Share sale and purchase agreement, future contingent consideration	39,500
Gain on sale of assets		$ 9,421	$ 600	$ 9,421	$ 600
Share Sale And Purchase Agreement, Contingent Consideration, Tranche One
Business Combination, Consideration Transferred, Equity Interest [Line Items]
Share sale and purchase agreement, future contingent consideration	12,500
Share Sale And Purchase Agreement, Contingent Consideration, Tranche Two
Business Combination, Consideration Transferred, Equity Interest [Line Items]
Share sale and purchase agreement, future contingent consideration	9,000
Share Sale And Purchase Agreement, Contingent Consideration, Tranche Three
Business Combination, Consideration Transferred, Equity Interest [Line Items]
Share sale and purchase agreement, future contingent consideration	9,000
Share Sale And Purchase Agreement, Contingent Consideration, Tranche Four
Business Combination, Consideration Transferred, Equity Interest [Line Items]
Share sale and purchase agreement, future contingent consideration	$ 9,000

Net Income (Loss) Per Share

6 Months Ended

Jun. 30, 2026

Earnings Per Share [Abstract]

Net Income (Loss) Per Share


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
	(In thousands, except per share data)
Numerator:
Net income (loss) allocable to common stockholders	$	184,775	$	(87,740)	$	(40,799)	$	(198,346)




Denominator:
Weighted average number of shares outstanding:
Basic	593,441		478,068		550,060		476,881
Restricted stock units(1)	11,272		—		—		—
Shares issuable assuming conversion of 3.125% Convertible Senior Notes(2)	—		—		—		—
Diluted	604,713		478,068		550,060		476,881
Net income (loss) per share:
Basic	$	0.31	$	(0.18)	$	(0.07)	$	(0.42)
Diluted	$	0.31	$	(0.18)	$	(0.07)	$	(0.42)

__________________________________

On March 10, 2026 the Company launched and priced a registered underwritten public offering of 112.1 million shares of common stock, par value $0.01, resulting in net proceeds to Kosmos of approximately $206.4 million. The offering closed on March 12, 2026.

Leases (Tables)

6 Months Ended

Jun. 30, 2026

Leases [Abstract]

Schedule of Other Information Leases

Other information related to operating and finance leases at June 30, 2026 and December 31, 2025, is as follows:


	June 30, 2026		December 31, 2025
	(In thousands, except lease term discount rate)
Balance sheet classifications
Operating leases
Other assets (right-of-use assets)	$	8,705	$	10,059
Accrued liabilities (current maturities of leases)	3,060		2,777
Other long-term liabilities (non-current maturities of leases)	7,852		9,438
Finance leases
Property and equipment, net(1)	69,454		—
Accrued liabilities	73,203		—

Schedule of Future Minimum Rental Commitments

Future minimum rental commitments under our leases as of June 30, 2026, are as follows:


	Operating Leases(1)		Financing Leases(1)
	(In thousands)
2026(2)	$	2,017	$	24,504
2027	3,951		52,514
2028	3,744		—
2029	3,176		—
2030	—		—
Thereafter	—		—
Total undiscounted lease payments	$	12,888	$	77,018
Less: Imputed interest	(1,976)		(3,815)
Total lease liabilities	$	10,912	$	73,203

__________________________________

(2) Represents the period July 1, 2026 through December 31, 2026

Property and Equipment

6 Months Ended

Jun. 30, 2026

Property, Plant, and Equipment [Abstract]

Property and Equipment

Property and equipment is stated at cost and consisted of the following:


	June 30, 2026		December 31, 2025
	(In thousands)
Oil and gas properties:
Proved properties	$	7,763,259	$	8,301,679
Unproved properties	210,786		210,161
Total oil and gas properties	7,974,045		8,511,840
Accumulated depletion	(4,624,781)		(4,780,826)
Oil and gas properties, net	3,349,264		3,731,014

Other property	69,046		68,255
Accumulated depreciation	(66,784)		(65,485)
Other property, net	2,262		2,770

Property and equipment, net	$	3,351,526	$	3,733,784

We recorded depletion expense of $111.8 million and $141.7 million for the three months ended June 30, 2026 and 2025, respectively, and $223.5 million and $253.1 million for the six months ended June 30, 2026 and 2025, respectively. During the six months ended June 30, 2026, the decrease in oil and gas properties, net is primarily due to the sale of the Ceiba and Okume Complex production assets located in Block G offshore Equatorial Guinea in June 2026. See Note 3 - Acquisitions and Divestitures. Additions to our proved properties during the six months ended June 30, 2026 primarily related to infill development costs in the Jubilee Field in Ghana and at Winterfell-5 in the Gulf of America. Additionally, in February 2026, Tullow Oil plc, as Operator of the TEN partnership, executed the final Sale and Purchase Agreement enabling the partnership to acquire the TEN FPSO from MODEC, Inc. at the end of its current lease in 2027 for a gross purchase price of $205.0 million. As a result, proved property additions for the period ended June 30, 2026 include $88.2 million for our proportionate share of the finance lease asset, with a corresponding finance lease liability in accrued liabilities. These non-cash impacts are excluded from the statement of cash flows.

- Definition

The entire disclosure for property, plant, and equipment. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Derivative Financial Instruments - Schedule of Location of Gain (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Derivative instruments, Location of Gain/(Loss)
Total derivatives not designated as hedging instruments	$ 40,683	$ 15,469	$ (262,292)	$ 7,883
Provisional sales contracts \| Income Statement Location [Axis]: us-gaap:Revenues
Derivative instruments, Location of Gain/(Loss)
Total derivatives not designated as hedging instruments	(11,126)	(6,780)	(62,105)	(7,607)
Commodity \| Income Statement Location [Axis]: kos:GainLossOnCommodityDerivativeInstrumentsNetPretax
Derivative instruments, Location of Gain/(Loss)
Total derivatives not designated as hedging instruments	51,809	21,566	(200,187)	14,834
Interest rate \| Income Statement Location [Axis]: kos:InterestExpenseIncomeNet
Derivative instruments, Location of Gain/(Loss)
Total derivatives not designated as hedging instruments	$ 0	$ 683	$ 0	$ 656

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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-Subparagraph (a)(4)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4D

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-Subparagraph (a)(3)
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-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4D

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Business Segment Information - Schedule of Consolidated Capital Expenditures (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Segment Reporting [Abstract]
Oil and gas assets			$ 163,477	$ 172,766
Financing lease			14,951	0
Changes in capital accruals			5,473	(5,910)
Exploration expense, excluding unsuccessful well costs and leasehold impairments			8,982	13,577
Capitalized interest			(4,096)	(8,510)
Other			7,745	372
Total consolidated capital expenditures, net	$ 105,052	$ 86,107	$ 196,532	$ 172,295

Leases - Narrative (Details)	Jun. 30, 2026
Minimum
Lessee, Lease, Description [Line Items]
Operating lease, initial term	1 year
Maximum
Lessee, Lease, Description [Line Items]
Operating lease, initial term	10 years

Fair Value Measurements - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
Fair Value Measurements - Narrative (Details) - USD ($)	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Jan. 31, 2026	Dec. 31, 2025	Dec. 31, 2024	Sep. 30, 2024	Mar. 31, 2024	Oct. 31, 2021	Mar. 31, 2021	Apr. 30, 2019
Fair Value Measurements
Contribution to decommissioning trust fund			$ 11,600,000	$ 11,500,000
Impairment of long-lived assets	$ 0	$ 0	$ 0	$ 0
7.125% Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)												7.125%
7.750% Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)										7.75%
7.500% Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)											7.50%
8.750% Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)								8.75%
3.125% Convertible Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)	3.125%		3.125%			3.125%	3.125%		3.125%
11.250% Senior Secured Bonds \| Senior Secured Bond
Fair Value Measurements
Interest rate (as a percent)					11.25%

Leases - Schedule of Future Minimum Rental Commitments (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Operating Leases
2026	$ 2,017
2027	3,951
2028	3,744
2029	3,176
2030	0
Thereafter	0
Total undiscounted lease payments	12,888
Less: Imputed interest	(1,976)
Total lease liabilities	10,912
Financing Leases
2026	24,504
2027	52,514
2028	0
2029	0
2030	0
Thereafter	0
Total undiscounted lease payments	77,018
Less: Imputed interest	(3,815)
Total lease liabilities	$ 73,203	$ 0

Debt - Schedule of Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Jan. 31, 2026	Dec. 31, 2025	Dec. 31, 2024	Sep. 30, 2024	Mar. 31, 2024	Oct. 31, 2021	Mar. 31, 2021	Apr. 30, 2019
Line of Credit Facility [Line Items]
Total long-term debt	$ 2,719,676		$ 3,100,274
Unamortized deferred financing costs and discounts	(47,501)		(47,515)
Total debt, net	2,672,175		3,052,759
Less: Current maturities of long-term debt	(145,303)		(132,143)
Long-term debt, net	2,526,872		2,920,616
Senior Notes
Line of Credit Facility [Line Items]
Unamortized deferred financing costs and discounts	(8,000)		(10,400)
Facility \| Revolving credit facility
Line of Credit Facility [Line Items]
Total long-term debt	800,000
Unamortized deferred financing costs and discounts	(21,700)		(24,300)
Facility \| Revolving credit facility
Line of Credit Facility [Line Items]
Total long-term debt	773,000		1,200,000
7.125% Senior Notes \| Senior Notes
Line of Credit Facility [Line Items]
Interest rate (as a percent)									7.125%
Total long-term debt	0		100,000
7.750% Senior Notes \| Senior Notes
Line of Credit Facility [Line Items]
Interest rate (as a percent)							7.75%
Total long-term debt	99,973		350,000
7.500% Senior Notes \| Senior Notes
Line of Credit Facility [Line Items]
Interest rate (as a percent)								7.50%
Total long-term debt	400,274		400,274
8.750% Senior Notes \| Senior Notes
Line of Credit Facility [Line Items]
Interest rate (as a percent)					8.75%
Total long-term debt	$ 500,000		$ 500,000
3.125% Convertible Senior Notes \| Senior Notes
Line of Credit Facility [Line Items]
Interest rate (as a percent)	3.125%		3.125%	3.125%		3.125%
Total long-term debt	$ 400,000		$ 400,000
Unamortized deferred financing costs and discounts	(8,000)		(9,000)
11.250% Senior Secured Bonds \| Senior Secured Bond
Line of Credit Facility [Line Items]
Interest rate (as a percent)		11.25%
Total long-term debt	350,000		0
Unamortized deferred financing costs and discounts	6,300		800
GoA Term Loan Facility \| Secured Debt
Line of Credit Facility [Line Items]
Total long-term debt	196,429		150,000
Unamortized deferred financing costs and discounts	$ 3,500		$ 3,000

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 102,137	$ 91,518
Restricted cash	23,505	0
Receivables	113,022	103,472
Inventories	139,947	172,640
Prepaid expenses and other	13,673	12,428
Derivatives	459	47,816
Total current assets	392,743	427,874
Property and equipment, net	3,351,526	3,733,784
Other assets:
Restricted cash	30,589	26,226
Long-term receivables	472,897	458,793
Deferred tax assets	2,757	3,946
Derivatives	2,335	2,681
Other	57,300	43,322
Total assets	4,310,147	4,696,626
Current liabilities:
Accounts payable	161,981	202,555
Accrued liabilities	343,879	237,609
Current maturities of long-term debt	145,303	132,143
Derivatives	11,633	0
Total current liabilities	662,796	572,307
Long-term liabilities:
Long-term debt, net	2,526,872	2,920,616
Derivatives	5,129	0
Asset retirement obligations	203,444	327,016
Deferred tax liabilities	177,375	305,924
Other long-term liabilities	29,634	42,173
Total long-term liabilities	2,942,454	3,595,729
Stockholders’ equity:
Preference shares, $0.01 par value; 200,000,000 authorized shares; zero issued at June 30, 2026 and December 31, 2025	0	0
Common stock, $0.01 par value; 2,000,000,000 authorized shares; 638,126,969 and 522,590,223 issued at June 30, 2026 and December 31, 2025, respectively	6,381	5,226
Additional paid-in capital	2,758,578	2,542,627
Accumulated deficit	(1,823,055)	(1,782,256)
Treasury stock, at cost, 44,263,269 shares at June 30, 2026 and December 31, 2025, respectively	(237,007)	(237,007)
Total stockholders’ equity	704,897	528,590
Total liabilities and stockholders’ equity	$ 4,310,147	$ 4,696,626

Debt - GTA Nordic Bonds (Details) - USD ($)			1 Months Ended	3 Months Ended	6 Months Ended
Debt - GTA Nordic Bonds (Details) - USD ($)	Jan. 31, 2026	Sep. 24, 2024	Jan. 31, 2026	Mar. 31, 2026	Jun. 30, 2026	Jun. 30, 2025	Oct. 31, 2021
Debt Instrument [Line Items]
Repayments of senior notes					$ 347,184,000	$ 0
11.250% Senior Secured Bonds \| Senior Secured Bond
Debt Instrument [Line Items]
Debt, face amount	$ 350,000,000.0		$ 350,000,000.0
Interest rate (as a percent)	11.25%		11.25%
Redemption price percentage (as a percent)			100.00%
Exercise put option, repurchased	90.00%
Restricted cash minimum liquidity requirement increases, non current			$ 17,500,000
Restricted cash minimum liquidity requirement			5.00%
Debt instrument, asset coverage ratio	1.25		1.25
11.250% Senior Secured Bonds \| Senior Secured Bond \| Debt Instrument, Redemption, Change Of Control
Debt Instrument [Line Items]
Redemption price percentage (as a percent)	101.00%
7.750% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount							$ 400,000,000.0
Interest rate (as a percent)							7.75%
Repayments of senior notes		$ 50,000,000.0		$ 249,800,000	$ 250,000,000.0
Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Repayment of debt			$ 100,000,000.0

Fair Value Measurements - Schedule of Costs and Fair Values of Investments in Debt Securities Held in Decommissioning Trust Fund (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Cost
Less than 5 years	$ 35,616	$ 23,565
5 years to 10 years	0	0
Due after 10 years	0	0
Total	35,616	23,565
Estimated Fair Value
Less than 5 years	35,652	23,707
5 years to 10 years	0	0
Due after 10 years	0	0
Total	$ 35,652	$ 23,707

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2026	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2026	Jun. 30, 2025
Revenues and other income:
Oil and gas revenue	$ 607,253		$ 392,635		$ 977,981	$ 682,770
Gain on sale of assets	9,421		600		9,421	600
Other income, net	361		283		530	579
Total revenues and other income	617,035		393,518		987,932	683,949
Costs and expenses:
Oil and gas production	179,429		243,118		310,024	410,426
Exploration expenses	3,197		4,069		22,941	13,738
General and administrative	19,263		19,074		46,973	45,329
Depletion, depreciation and amortization	120,501		151,268		240,374	271,935
Interest and other financing costs, net	53,700		54,834		112,502	106,676
Derivatives, net	(51,809)		(21,566)		200,187	(14,834)
Other expenses, net	10,281		6,481		13,545	8,470
Total costs and expenses	334,562		457,278		946,546	841,740
Income (loss) before income taxes	282,473		(63,760)		41,386	(157,791)
Income tax expense	97,698		23,980		82,185	40,555
Net income (loss)	$ 184,775	$ (225,574)	$ (87,740)	$ (110,606)	$ (40,799)	$ (198,346)
Net income (loss) per share:
Basic (in dollars per share)	$ 0.31		$ (0.18)		$ (0.07)	$ (0.42)
Diluted (in dollars per share)	$ 0.31		$ (0.18)		$ (0.07)	$ (0.42)
Weighted average number of shares used to compute net income (loss) per share:
Basic (in shares)	593,441		478,068		550,060	476,881
Diluted (in shares)	604,713		478,068		550,060	476,881

Debt

6 Months Ended

Jun. 30, 2026

Debt Disclosure [Abstract]

Debt


	June 30, 2026		December 31, 2025
	(In thousands)
Outstanding debt principal balances:
Facility	$	773,000	$	1,200,000
7.125% Senior Notes	—		100,000
7.750% Senior Notes	99,973		350,000
7.500% Senior Notes	400,274		400,274
8.750% Senior Notes	500,000		500,000
3.125% Convertible Senior Notes	400,000		400,000
11.250% Senior Secured Bonds	350,000		—
GoA Term Loan Facility	196,429		150,000
Total long-term debt	2,719,676		3,100,274
Unamortized deferred financing costs and discounts(1)	(47,501)		(47,515)
Total debt, net	2,672,175		3,052,759
Less: Current maturities of long-term debt	(145,303)		(132,143)
Long-term debt, net	$	2,526,872	$	2,920,616

Facility

The Facility supports our oil and gas exploration, appraisal and development programs and corporate activities. The amount of funds available to be borrowed under the Facility, also known as the borrowing base amount, is determined every March and September. In April 2026, during the Spring 2026 redetermination, the Company’s lending syndicate approved a borrowing base at approximately $1.25 billion. The borrowing base amount was based on the sum of the net present values of net cash flows and relevant capital expenditures reduced by certain percentages as well as value attributable to certain assets’ reserves and/or resources in the Company’s production assets in Ghana and Equatorial Guinea. Following the closing of the sale of all our participating interest in the Ceiba Field and Okume Complex production assets located in Block G offshore Equatorial Guinea on June 16, 2026, the Company’s production assets in Equatorial Guinea are no longer included in the borrowing base amount, and, as agreed with the lending syndicate, the borrowing base has been reduced to approximately $1.2 billion. As of June 30, 2026, borrowings under the Facility totaled approximately $0.8 billion and the undrawn availability under the Facility was approximately $440 million. Final maturity of the Facility is December 31, 2029.

Interest on the Facility is the aggregate of the applicable margin (4.00% to 5.50%, depending on the length of time that has passed from the date the Facility was entered into), plus the term SOFR reference rate administered by CME Group Benchmark Administration Limited for the relevant period published. Interest is payable on the last day of each interest period (and, if the interest period is longer than six months, on the dates falling at six-month intervals after the first day of the interest period). We pay commitment fees on the undrawn and unavailable portion of the total commitments, if any. Commitment fees are equal to 30% per annum of the then-applicable respective margin when a commitment is available for utilization and, equal to 20% per annum of the then-applicable respective margin when a commitment is not available for utilization. We recognize interest expense in accordance with ASC 835 — Interest, which requires interest expense to be recognized using the effective interest method. We determined the effective interest rate based on the estimated level of borrowings under the Facility.

The Facility provides a revolving credit and letter of credit facility. As of June 30, 2026, we had no letters of credit issued under the Facility.

When our debt cover ratio exceeds 2.50x, we are required under the Facility to maintain a restricted cash balance that is sufficient to meet the payment of interest and fees for the next six-month period on the 7.750% Senior Notes, the 7.500% Senior Notes, the 8.750% Senior Notes and the 3.125% Convertible Senior Notes or the Facility, whichever is greater. During the first quarter of 2025, the Facility lenders waived the requirement to maintain a restricted cash balance until the financial covenant test date to be calculated on March 31, 2026. During the second quarter of 2026, the Facility lenders agreed to reduce the amount of the required restricted cash balance to three months of interest and fees until the September 30, 2026 financial

covenant test date, after which the amount of the required restricted cash balance will be determined as usual. Our debt cover ratio for the most recent March 31, 2026 financial covenant test date exceeded 2.50x and the estimated restricted cash funding requirement is approximately $23.5 million. As of June 30, 2026 we have funded approximately $23.5 million into the debt service reserve account as required under the terms of the Facility.

In July 2025, the Company and the Facility lenders agreed to amend the debt cover ratio required under the Facility. The amendment made this covenant less restrictive for the following two scheduled financial covenant assessment dates, up to a maximum of 4.0x and 4.25x, respectively, and thereafter returned to the originally agreed upon ratio of 3.50x for assessment dates thereafter. In February 2026, we further amended the debt cover ratio calculation through September 2026. This most recent amendment makes the covenant less restrictive for the following two scheduled financial covenant assessment dates, up to a maximum of 4.5x and 4.25x respectively, and for purposes of the financial covenant assessment date in March 2026, the calculation was made excluding the Company’s Mauritania and Senegal business unit. The debt cover ratio returns to the originally agreed upon ratio of 3.5x for assessment dates thereafter.

We were in compliance with the financial covenants, as amended, contained in the Facility as of the most recent assessment date. The Facility contains customary cross default provisions.

7.125% Senior Notes due 2026

In April 2019, the Company issued $650.0 million of 7.125% Senior Notes and received net proceeds of approximately $640.0 million after deducting fees. The 7.125% Senior Notes mature on April 4, 2026.

On September 24, 2024, the Company completed the repurchase of an aggregate principal amount of $400.0 million of the 7.125% Senior Notes pursuant to the Company’s cash tender offers for portions of the 7.125% Senior Notes, the 7.750% Senior Notes, and the 7.500% Senior Notes announced on September 9, 2024 (the “Tender Offers”). In October 2025, we used proceeds from funding of the first tranche under the GoA Term Loan Facility to complete the partial redemption of an additional aggregate principal amount of $150.0 million of the 7.125% Senior Notes. In January 2026, we used the proceeds from funding the second tranche under the GoA Term Loan Facility, together with cash on hand, to complete the redemption of the remaining outstanding balance amount of $100.0 million of the 7.125% Senior Notes.

7.750% Senior Notes due 2027

In October 2021, the Company issued $400.0 million of 7.750% Senior Notes and received net proceeds of approximately $395.0 million after deducting fees. The 7.750% Senior Notes mature on May 1, 2027. Interest is payable in arrears each May 1 and November 1, commencing on May 1, 2022. The 7.750% Senior Notes are senior, unsecured obligations of Kosmos Energy Ltd. and rank equal in right of payment with all of its existing and future senior indebtedness (including all borrowings under the 7.500% Senior Notes, the 8.750% Senior Notes and the 3.125% Convertible Senior Notes) and rank effectively junior in right of payment to all of its existing and future secured indebtedness (including all borrowings under the Facility). The 7.750% Senior Notes are guaranteed on a senior, unsecured basis by certain subsidiaries owning the Company's Gulf of America assets, and on a subordinated, unsecured basis by certain subsidiaries that borrow under, or guarantee, the Facility and that guarantee the 7.500% Senior Notes, the 8.750% Senior Notes and the 3.125% Convertible Senior Notes.

On September 24, 2024, the Company completed the repurchase of an aggregate principal amount of $50.0 million of the 7.750% Senior Notes pursuant to the Tender Offers. In the first half of 2026, the Company used a portion of the net proceeds from the Nordic bond offering to fund the repurchase of an aggregate principal amount of $250.0 million of the 7.750% Senior Notes pursuant to the Company’s cash tender offer announced on January 12, 2026 and open market repurchases. The 7.750% Senior Notes contain customary cross default provisions.

7.500% Senior Notes due 2028

In March 2021, the Company issued $450.0 million of 7.500% Senior Notes and received net proceeds of approximately $444.4 million after deducting fees. The 7.500% Senior Notes mature on March 1, 2028. Interest is payable in arrears each March 1 and September 1, commencing on September 1, 2021. The 7.500% Senior Notes are senior, unsecured obligations of Kosmos Energy Ltd. and rank equal in right of payment with all of its existing and future senior indebtedness (including all borrowings under the 7.750% Senior Notes, the 8.750% Senior Notes and the 3.125% Convertible Senior Notes) and rank effectively junior in right of payment to all of its existing and future secured indebtedness (including all borrowings under the Facility). The 7.500% Senior Notes are guaranteed on a senior, unsecured basis by certain subsidiaries owning the Company's Gulf of America assets, and on a subordinated, unsecured basis by certain subsidiaries that borrow under, or guarantee, the Facility and that guarantee the 7.750% Senior Notes, the 8.750% Senior Notes and the 3.125% Convertible Senior Notes.

On September 24, 2024, the Company completed the repurchase of an aggregate principal amount of approximately $49.7 million of the 7.500% Senior Notes pursuant to the Tender Offers. The 7.500% Senior Notes contain customary cross default provisions.

8.750% Senior Notes due 2031

In September 2024, the Company issued $500.0 million of 8.750% Senior Notes (the “8.750% Senior Notes”) and received net proceeds of approximately $494.9 million after deducting fees. The 8.750% Senior Notes mature on October 1, 2031. Interest is payable in arrears each April 1 and October 1, commencing on April 1, 2025. The 8.750% Senior Notes are senior, unsecured obligations of Kosmos Energy Ltd. and rank equal in right of payment with all of its existing and future senior indebtedness (including all borrowings under the 7.750% Senior Notes, the 7.500% Senior Notes and the 3.125% Convertible Senior Notes) and rank effectively junior in right of payment to all of its existing and future secured indebtedness (including all borrowings under the Facility). The 8.750% Senior Notes are guaranteed on a senior, unsecured basis by certain subsidiaries owning the Company’s Gulf of America assets and on a subordinated, unsecured basis by certain subsidiaries that borrow under, or guarantee, the Facility and that guarantee the 7.750% Senior Notes, the 7.500% Senior Notes and the 3.125% Convertible Senior Notes. The 8.750% Senior Notes contain customary cross default provisions.

3.125% Convertible Senior Notes due 2030

In March 2024, the Company issued $400.0 million of 3.125% Convertible Senior Notes (the “3.125% Convertible Senior Notes”) and received net proceeds of $390.4 million after deducting fees. The 3.125% Convertible Senior Notes mature on March 15, 2030, unless earlier converted, redeemed or repurchased. Interest is payable in arrears each March 15 and September 15, commencing September 15, 2024. The 3.125% Convertible Senior Notes are senior, unsecured obligations of Kosmos Energy Ltd. and rank equal in right of payment with all of its existing and future senior indebtedness (including all borrowings under the 7.750% Senior Notes, the 7.500% Senior Notes and the 8.750% Senior Notes) and rank effectively junior in right of payment to all of its existing and future secured indebtedness (including all borrowings under the Facility, to the extent of the value of the assets securing such indebtedness). The 3.125% Convertible Senior Notes are guaranteed on a senior, unsecured basis by certain of our existing subsidiaries that guarantee on a senior basis the 7.750% Senior Notes, the 7.500% Senior Notes and the 8.750% Senior Notes, and, in certain circumstances, certain of our other existing or future subsidiaries. The 3.125% Convertible Senior Notes are guaranteed on a subordinated, unsecured basis by certain of our existing subsidiaries that borrow under or guarantee the Facility and guarantee on a subordinated basis the 7.750% Senior Notes, the 7.500% Senior Notes and the 8.750% Senior Notes, and, in certain circumstances, certain of our other existing or future subsidiaries.

The 3.125% Convertible Senior Notes indenture contains customary terms and covenants and cross default provisions.

The Company recorded the 3.125% Convertible Senior Notes, including the debt itself and all embedded derivatives, at cost less debt issuance costs of $9.6 million and has presented the 3.125% Convertible Senior Notes as a single financial instrument in Long-term debt, net in our consolidated balance sheet. No portion of the embedded derivatives required bifurcation from the host debt contract. As of June 30, 2026, the effective annual interest rate on the 3.125% Convertible Senior Notes is approximately 3.70%, including amortization of debt issuance costs.

The conversion rate for the 3.125% Convertible Senior Notes is initially 142.4501 shares of our common stock per $1,000 principal amount of 3.125% Convertible Senior Notes (which is the equivalent to an initial conversion price of approximately $7.02 per share of our common stock), subject to adjustments. As of June 30, 2026, no shares have been converted.

Capped Call Transactions

In connection with the issuance of the 3.125% Convertible Senior Notes, the Company used $49.8 million of the net proceeds from the issuance of the 3.125% Convertible Senior Notes to enter into capped call transactions (the “Capped Call Transactions”). The Capped Call Transactions are generally expected to reduce potential dilution to holders of our common stock upon any conversion of the 3.125% Convertible Senior Notes and/or offset any cash payments that we are required to make in excess of the principal amount of any 3.125% Convertible Senior Notes that are converted, as the case may be, with such reduction and/or offset subject to a cap.

The Capped Call Transactions qualify for a derivative scope exception as they are indexed to our common stock and are not required to be accounted for as a separate derivative. Consequently, the Capped Call Transactions have been included as a net reduction to additional-paid-in-capital within stockholders’ equity in our consolidated balance sheet and do not require subsequent remeasurement.

GoA Term Loan Facility

On September 24, 2025, the Company entered into a senior secured term loan credit agreement secured by first priority liens on all of the Company’s Gulf of America assets (as defined in the credit agreement). The GoA Term Loan Facility is structured in two tranches, with the first tranche consisting of a four-year term loan in an aggregate principal amount of $150.0 million, which was funded on October 1, 2025 with net proceeds received of $147.2 million after deducting fees and other expenses, and a second tranche of an additional $100.0 million, which funded in January 2026 with net proceeds received of $98.5 million after deducting fees and expenses.

The net proceeds were used, together with cash on hand, to fund the redemption of $250.0 million in aggregate of the 7.125% Senior Notes due 2026. On March 24, 2026, we made a voluntary prepayment of $53.6 million against the GoA Term Loan. On May 1, 2026, the GoA Term Loan Facility was amended to apply this prepayment in full satisfaction of the scheduled principal amount due on the first scheduled amortization payment date on June 30, 2026, and then ratably to all remaining scheduled principal payments of the outstanding loans. The amendment also deferred all future scheduled amortization payment dates in 2026, 2027 and 2028 such that they will now be due on October 1, January 1, April 1 and July 1 in each of 2026, 2027 and 2028. As a result of the amendment, there is only one remaining scheduled amortization payment in 2026 to be paid on October 1, 2026.

Interest on outstanding loans under the GoA Term Loan Facility is payable quarterly in arrears at a rate per annum equal to 3.75% plus the term SOFR reference rate administered by CME Group Benchmark Administration Limited for the relevant period published. The GoA Term Loan Facility matures in 2029.

The GoA Term Loan Facility contains customary affirmative and negative covenants, including covenants that affect our ability to incur additional indebtedness, create liens, merge, dispose of assets, and make distributions, dividends, investments or capital expenditures, among other things. The GoA Term Loan Facility requires the Company to maintain certain financial covenants including:

•the GoA field life coverage ratio (as defined in the glossary), not less than 1.50x; and

•the GoA net leverage ratio (as defined in the glossary), not more than 3.50x.

The GoA Term Loan Facility also includes certain representations and warranties, indemnities and events of default that, subject to materiality thresholds and grace periods, arise as a result of a payment of default, failure to comply with covenants, material inaccuracy of representation or warranty, and certain bankruptcy or insolvency proceedings. If there is an event of default, all or any portion of the outstanding indebtedness may be immediately due and payable and other rights may be exercised including against the collateral. We were in compliance with the covenants, representations and warranties contained in the GoA Term Loan Facility as of the most recent assessment date.

GTA Nordic bonds

In January 2026 the Company issued $350.0 million of 11.250% senior secured bonds due 2031 in the Nordic market (the “GTA Nordic bonds”). In the first quarter of 2026, the Company used the net proceeds from the Nordic bond offering to fund the repurchase of an aggregate principal amount of $249.8 million of the 7.750% Senior Notes pursuant to the Company’s cash tender offer announced on January 12, 2026 and open market repurchases, and to make a voluntary early principal repayment of $100.0 million on outstanding borrowings under the Facility.

The GTA Nordic bonds mature in January 2031. Interest is payable semi-annually in arrears each July 29 and January 29, commencing on July 29, 2026. The GTA Nordic bonds were issued by Kosmos Energy GTA Holdings, a wholly-owned subsidiary of Kosmos Energy Ltd., and are fully and unconditionally guaranteed by the Company and the Company’s wholly-owned subsidiaries, Kosmos Energy Tortue Finance, Kosmos Energy Senegal, Kosmos Energy Investments Senegal Limited and Kosmos Energy Mauritania. The GTA Nordic bonds are also guaranteed on an unsecured basis by certain of the Company’s subsidiaries that also guarantee the Company’s existing senior unsecured notes.

At any time prior to July 29, 2028, the Company may, on any one or more occasions, redeem all or part of the GTA Nordic bonds at a redemption price equal to 100%, plus any accrued and unpaid interest, and plus a “make-whole” premium. On and after July 29, 2028, the Company may redeem all or part of the GTA Nordic bonds at the following redemption prices (expressed as a percentage of principal amount), plus accrued and unpaid interest, if any, on the notes redeemed:


Year	Percentage
July 29, 2028 to, but not including, July 29, 2029	105.625	%
July 29, 2029 to, but not including, July 29, 2030	103.375	%
July 29, 2030 and thereafter	100.000	%

If the Company’s shares are no longer listed on the New York Stock Exchange or upon the occurrence of a change of control event, as defined in the Bond Terms for the GTA Nordic bonds, each Nordic bondholder shall have a right to require that the Company repurchase all or some of the GTA Nordic bonds held by that Nordic bondholder (a “Put Option”) at a repurchase price equal to 101% of the principal amount, plus accrued and unpaid interest to, but excluding, the date of repurchase. If more than 90% of the outstanding GTA Nordic bonds have been repurchased as a result of the exercise of the Put Option, the Company will be entitled to repurchase all the remaining GTA Nordic bonds at a price equal to 101% of the principal amount.

The Bond Terms governing the GTA Nordic bonds restrict the ability of Kosmos Energy GTA Holdings, Kosmos Energy Tortue Finance, Kosmos Energy Senegal, Kosmos Energy Investments Senegal Limited and Kosmos Energy Mauritania to, among other things: incur or guarantee additional indebtedness, create liens, sell assets, enter into transactions with affiliates, or effect certain consolidations, mergers or amalgamations.

The Bond Terms governing the GTA Nordic bonds also require Kosmos Energy GTA Holdings to maintain certain financial covenants including:

•Minimum Liquidity (as defined in the Bond Terms) of not less than $17.5 million or 5% of the outstanding GTA Nordic bonds, whichever is greater; and

•an Asset Coverage Ratio (as defined in the Bond Terms) of at least 1.25x

We were in compliance with the financial covenants as of the most recent assessment date. The GTA Nordic bonds contains customary cross default provisions.

Principal Debt Repayments

At June 30, 2026, the estimated repayments of debt during the five fiscal year periods and thereafter are as follows:


	Payments Due by Year
	Total		2026(2)		2027		2028		2029		2030		Thereafter
	(In thousands)
Principal debt repayments(1)	$	2,719,676	$	15,110	$	304,848	$	718,857	$	430,861	$	400,000	$	850,000

__________________________________

(2)Represents payments for the period July 1, 2026 through December 31, 2026.

Interest and other financing costs, net

Interest and other financing costs, net incurred during the periods is comprised of the following:


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
	(In thousands)
Interest expense	$	60,995	$	55,825	$	122,051	$	111,671
Amortization—deferred financing costs	2,705		1,889		5,297		3,773
Debt modifications and extinguishments	136		—		(1,081)		—
Capitalized interest	(2,229)		(4,316)		(4,096)		(8,510)
Deferred interest	(8,239)		249		(10,954)		(1,793)
Interest income	(8,265)		(7,158)		(16,140)		(15,253)
Other, net	8,597		8,345		17,425		16,788
Interest and other financing costs, net	$	53,700	$	54,834	$	112,502	$	106,676

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
-Section S45
-Paragraph 1
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-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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-Name Accounting Standards Codification
-Section S50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480657/210-10-S50-9

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 8A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8A

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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Reference 20: http://www.xbrl.org/2003/role/disclosureRef
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Reference 21: http://www.xbrl.org/2003/role/disclosureRef
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Reference 22: http://www.xbrl.org/2003/role/disclosureRef
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Reference 23: http://www.xbrl.org/2003/role/disclosureRef
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Reference 24: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 25: http://www.xbrl.org/2003/role/disclosureRef
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Reference 26: http://www.xbrl.org/2003/role/disclosureRef
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Reference 27: http://www.xbrl.org/2003/role/disclosureRef
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Reference 28: http://www.xbrl.org/2003/role/disclosureRef
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Reference 29: http://www.xbrl.org/2003/role/disclosureRef
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Reference 30: http://www.xbrl.org/2003/role/disclosureRef
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Reference 31: http://www.xbrl.org/2003/role/disclosureRef
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Reference 32: http://www.xbrl.org/2003/role/disclosureRef
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Reference 33: http://www.xbrl.org/2003/role/disclosureRef
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Reference 34: http://www.xbrl.org/2003/role/disclosureRef
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Reference 35: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Income Taxes - Narrative (Details)	3 Months Ended		6 Months Ended
Income Taxes - Narrative (Details)	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Income Tax Disclosure [Abstract]
Effective tax rate (as a percent)	35.00%	(38.00%)	199.00%	(26.00%)

Additional Financial Information - Schedule of Changes in Asset Retirement Obligations (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2026 USD ($)
Asset retirement obligations:
Beginning asset retirement obligations	$ 337,497
Liabilities incurred during period	3,051
Liabilities settled during period	(143,166)
Revisions in estimated retirement obligations	242
Accretion expense	15,587
Ending asset retirement obligations	$ 213,211

Suspended Well Costs

6 Months Ended

Jun. 30, 2026

Oil and Gas Disclosure [Abstract]

Suspended Well Costs

The following table reflects the Company’s capitalized exploratory well costs on drilled wells as of and during the six months ended June 30, 2026.


	June 30, 2026
	(In thousands)
Beginning balance	$	73,141
Additions to capitalized exploratory well costs pending the determination of proved reserves	4,985
Reclassification due to determination of proved reserves	—
Capitalized exploratory well costs charged to expense	—
Ending balance	$	78,126


	June 30, 2026		December 31, 2025
	(In thousands, except project counts)
Exploratory well costs capitalized for a period of one year or less	$	—	$	—
Exploratory well costs capitalized for a period of one to five years	78,126		73,141
Exploratory well costs capitalized for a period of six to ten years	—		—
Ending balance	$	78,126	$	73,141
Number of projects that have exploratory well costs that have been capitalized for a period greater than one year	1		1

As of June 30, 2026, the projects with exploratory well costs capitalized for more than one year since the completion of drilling are related to the Tiberius discovery in Keathley Canyon Block 964 in the Outer Wilcox play in the Gulf of America.

Tiberius Discovery — In July 2023, we spud the Tiberius infrastructure-led exploration prospect located in Block 964 of Keathley Canyon in the Gulf of America, which encountered hydrocarbon pay. Initial fluid and core analysis supports the production potential of the well, with characteristics analogous with similar nearby discoveries in the Wilcox trend. In July 2026, we completed a farm-out of Tiberius, reducing our interest to 33.34%. The Tiberius project is being progressed as a phased development. A production handling agreement for the Oxy operated Lucius platform was signed in the third quarter of 2025, contracts for the fabrication and installation of the Tiberius subsea production system have been executed and a final investment decision for the development was achieved by the partnership in March 2026.

Additional Financial Information

6 Months Ended

Jun. 30, 2026

Additional Financial Information [Abstract]

Additional Financial Information

Accrued Liabilities

Accrued liabilities consisted of the following:


	June 30, 2026		December 31, 2025
	(In thousands)
Accrued liabilities:
Exploration, development and production	$	43,793	$	57,007
Revenue payable	18,862		69,273
Current asset retirement obligations	9,767		10,481
Finance lease liability	73,203		—
General and administrative expenses	23,460		4,916
Interest	91,427		67,830
Income taxes	51,596		16,050
Taxes other than income	2,209		1,305
Derivatives	14,921		125
Other	14,641		10,622
Total	$	343,879	$	237,609

Asset Retirement Obligations

The following table summarizes the changes in the Company's asset retirement obligations as of and during the six months ended June 30, 2026:


	June 30, 2026
	(In thousands)
Asset retirement obligations:
Beginning asset retirement obligations	$	337,497
Liabilities incurred during period	3,051
Liabilities settled during period	(143,166)
Revisions in estimated retirement obligations	242
Accretion expense	15,587
Ending asset retirement obligations	$	213,211

The liabilities settled during 2026 primarily relate to the sale of the Ceiba and Okume Complex production assets located in Block G offshore Equatorial Guinea in June 2026. See Note 3 - Acquisitions and Divestitures.

Debt - Schedule of Interest and Other Financing Costs, Net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Debt Disclosure [Abstract]
Interest expense	$ 60,995	$ 55,825	$ 122,051	$ 111,671
Amortization—deferred financing costs	2,705	1,889	5,297	3,773
Debt modifications and extinguishments	136	0	(1,081)	0
Capitalized interest	(2,229)	(4,316)	(4,096)	(8,510)
Deferred interest	(8,239)	249	(10,954)	(1,793)
Interest income	(8,265)	(7,158)	(16,140)	(15,253)
Other, net	8,597	8,345	17,425	16,788
Interest and other financing costs, net	$ 53,700	$ 54,834	$ 112,502	$ 106,676

Additional Financial Information (Tables)

6 Months Ended

Jun. 30, 2026

Additional Financial Information [Abstract]

Schedule of Accrued Liabilities

Accrued liabilities consisted of the following:


	June 30, 2026		December 31, 2025
	(In thousands)
Accrued liabilities:
Exploration, development and production	$	43,793	$	57,007
Revenue payable	18,862		69,273
Current asset retirement obligations	9,767		10,481
Finance lease liability	73,203		—
General and administrative expenses	23,460		4,916
Interest	91,427		67,830
Income taxes	51,596		16,050
Taxes other than income	2,209		1,305
Derivatives	14,921		125
Other	14,641		10,622
Total	$	343,879	$	237,609

Schedule of Changes in Asset Retirement Obligations

The following table summarizes the changes in the Company's asset retirement obligations as of and during the six months ended June 30, 2026:


	June 30, 2026
	(In thousands)
Asset retirement obligations:
Beginning asset retirement obligations	$	337,497
Liabilities incurred during period	3,051
Liabilities settled during period	(143,166)
Revisions in estimated retirement obligations	242
Accretion expense	15,587
Ending asset retirement obligations	$	213,211

Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2026

Fair Value Disclosures [Abstract]

Schedule of Company's Assets and Liabilities that are Measured at Fair Value on a Recurring Basis


	Fair Value Measurements Using:
	Quoted Prices in
	Active Markets for		Significant Other		Significant
	Identical Assets		Observable Inputs		Unobservable Inputs
	(Level 1)		(Level 2)		(Level 3)		Total
	(In thousands)
June 30, 2026
Assets:
Commodity derivatives	$	—	$	2,794	$	—	$	2,794
Provisional sales contracts	—		857		—		857

Debt securities held in decommissioning trust fund	—		35,652		$	—	35,652
Liabilities:
Commodity derivatives	—		(16,762)		—		(16,762)


Total	$	—	$	22,541	$	—	$	22,541
December 31, 2025
Assets:
Commodity derivatives	$	—	$	50,497	$	—	$	50,497


Debt securities held in decommissioning trust fund	—		23,707		—		23,707




Total	$	—	$	74,204	$	—	$	74,204

Schedule of Costs and Fair Values of Investments in Debt Securities in Decommissioning Trust Fund


	Three Months Ended June 30,						Six Months Ended June 30,
Type of Security	Purchases		Net Proceeds (1)		Unrealized Gain (Loss)		Purchases		Net Proceeds (1)		Unrealized Gain (Loss)
	(In thousands)
2026
Debt securities	$	209	$	—	$	(18)	$	12,051	$	—	$	(106)
Cash and cash equivalents	—		(7)		—		—		1		—
Other(1)	—		156		—		—		181		—
Total	$	209	$	149	$	(18)	$	12,051	$	182	$	(106)
2025
Debt securities	$	198	$	—	$	22	$	12,406	$	—	$	131
Cash and cash equivalents	—		2		—		—		(745)		—
Other(1)	—		23		—		—		166		—
Total	$	198	$	25	$	22	$	12,406	$	(579)	$	131

(1) Represents net receivables relating to interest.


	June 30, 2026				December 31, 2025
	Cost		Estimated Fair Value		Cost		Estimated Fair Value
	(In thousands)
Less than 5 years	$	35,616	$	35,652	$	23,565	$	23,707
5 years to 10 years	—		—		—		—
Due after 10 years	—		—		—		—
Total	$	35,616	$	35,652	$	23,565	$	23,707

Schedule of Carrying Values and Fair Values of Financial Instruments that are not Carried at Fair Value

The following table presents the carrying values and fair values at June 30, 2026 and December 31, 2025:


	June 30, 2026				December 31, 2025
	Carrying Value		Fair Value		Carrying Value		Fair Value
	(In thousands)
7.125% Senior Notes	$	—	$	—	$	99,942	$	99,303
7.750% Senior Notes	99,747		99,456		348,757		321,394
7.500% Senior Notes	398,825		381,313		398,426		270,125
8.750% Senior Notes	495,866		409,555		495,564		283,575
3.125% Convertible Senior Notes	393,864		293,572		393,097		172,704
11.250% Senior Secured Bonds	350,000		359,482		—		—
GoA Term Loan Facility	196,429		196,429		150,000		150,000
Facility	773,000		773,000		1,200,000		1,200,000
Total	$	2,707,731	$	2,512,807	$	3,085,786	$	2,497,101

- Definition

Tabular disclosure of information about investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5B

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5B
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5B

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5B
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5B

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5B

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5

Reference 13: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5

Reference 14: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5

Reference 15: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)(4)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5

Reference 16: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5A

Reference 17: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5A

Reference 18: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5A

+ Details

Net Income (Loss) Per Share - Schedule of Reconciliation Between Compute Basic and Diluted Net Loss Per Share and Weighted Average Share Outstanding (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2026	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025	Dec. 31, 2024	Mar. 31, 2024
Numerator:
Net income (loss) allocable to common stockholders	$ 184,775	$ (225,574)	$ (87,740)	$ (110,606)	$ (40,799)	$ (198,346)
Weighted average number of shares outstanding:
Basic (in shares)	593,441		478,068		550,060	476,881
Restricted stock units (in shares)	11,272		0		0	0
Shares issuable assuming conversion of Convertible Senior Notes (in shares)	0		0		0	0
Diluted (in shares)	604,713		478,068		550,060	476,881
Net income (loss) per share:
Basic (in dollars per share)	$ 0.31		$ (0.18)		$ (0.07)	$ (0.42)
Diluted (in dollars per share)	$ 0.31		$ (0.18)		$ (0.07)	$ (0.42)
Outstanding restricted stock units excluded from the computations of diluted net income per share (in shares)	2,500		5,200		17,100	5,900
3.125% Convertible Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	3.125%				3.125%		3.125%	3.125%	3.125%

Debt - Schedule of Principal Debt Repayments (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Debt Disclosure [Abstract]
Total	$ 2,719,676	$ 3,100,274
2026	15,110
2027	304,848
2028	718,857
2029	430,861
2030	400,000
Thereafter	$ 850,000

Business Segment Information - Narrative (Details) - segment	3 Months Ended	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2026
Segment Reporting [Abstract]
Number of reportable segments	4	4

Receivables

6 Months Ended

Jun. 30, 2026

Receivables [Abstract]

Receivables

Receivables consisted of the following:


	June 30, 2026		December 31, 2025
	(In thousands)
Joint interest billings, net	$	13,780	$	17,255
Oil and gas sales	90,369		56,700
Other current receivables	8,873		29,517
Total receivables	$	113,022	$	103,472

Long-term receivables	$	472,897	$	458,793

The Company’s joint interest billings consist of receivables from partners with interests in common oil and gas properties operated by the Company for shared costs. Joint interest billings are classified as current and long-term receivables based on when collection is expected to occur.

Long-term receivables

In February 2019, Kosmos and BP signed Carry Advance Agreements with the national oil companies of Mauritania and Senegal obligating us to finance a portion of the respective national oil company’s share of certain development and production costs incurred for the GTA Phase 1 project through the Commercial Operations Date of the Gimi FLNG vessel. The Commercial Operations Date of the Gimi FLNG vessel was achieved in June 2025. As of June 30, 2026 and December 31, 2025, the balance due from the national oil companies including accrued interest was $450.9 million and $437.1 million, respectively, which is classified as Long-term receivables in our consolidated balance sheets. Interest income on the long-term notes receivable was $7.0 million and $6.2 million for the three months ended June 30, 2026 and 2025, respectively, and $13.8 million and $11.5 million for the six months ended June 30, 2026 and 2025.

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025
Statement of Cash Flows [Abstract]
Cash settlements on commodity hedges derivatives	$ (135.7)	$ 9.7

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025
Operating activities
Net loss	$ (40,799)	$ (198,346)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depletion, depreciation and amortization (including deferred financing costs)	245,671	275,708
Deferred income taxes	(1,268)	1,636
Unsuccessful well costs and leasehold impairments	13,959	162
Change in fair value of derivatives	262,292	(7,883)
Cash settlements on derivatives, net (including $(135.7) million and $9.7 million on commodity hedges during 2026 and 2025)	(198,684)	6,281
Equity-based compensation	14,064	15,707
Gain on sale of assets	(9,421)	(600)
Debt modifications and extinguishments	(1,081)	0
Other	(20,759)	(8,506)
Changes in assets and liabilities:
(Increase) decrease in receivables	(19,990)	70,659
Decrease in inventories and prepaid expenses	17,209	7,542
Increase (decrease) in accounts payable and accrued liabilities	20,373	(36,080)
Net cash provided by operating activities	281,566	126,280
Investing activities
Oil and gas assets	(163,477)	(172,766)
Proceeds on sale of assets	127,034	0
Notes receivable and other investing activities	(11,598)	(86,791)
Net cash used in investing activities	(48,041)	(259,557)
Financing activities
Borrowings under long-term debt	124,167	200,000
Payments on long-term debt	(504,738)	(100,000)
Net proceeds from issuance of senior notes and bonds	350,000	0
Repurchase and redemption of senior notes	(347,184)	0
Net proceeds from issuance of common stock	206,440	0
Payments on finance lease	(14,951)	0
Other financing costs	(8,772)	(1)
Net cash provided by (used in) financing activities	(195,038)	99,999
Net increase (decrease) in cash, cash equivalents and restricted cash	38,487	(33,278)
Cash, cash equivalents and restricted cash at beginning of period	117,744	85,277
Cash, cash equivalents and restricted cash at end of period	156,231	51,999
Supplemental cash flow information
Interest, net of capitalized interest	108,469	101,377
Income taxes, net of refund received	$ 47,908	$ 69,296

Equity-based Compensation - Schedule of Awards (Details) - LTIP shares in Thousands	6 Months Ended
	Jun. 30, 2026 $ / shares shares
Service Vesting Restricted Stock Units
Market / Service Vesting Restricted Stock Units
Outstanding at beginning of the period (in shares) \| shares	5,073
Granted (in shares) \| shares	5,275
Forfeited (in shares) \| shares	(864)
Vested (in shares) \| shares	(2,824)
Outstanding at end of the period (in shares) \| shares	6,660
Weighted-Average Grant-Date Fair Value
Outstanding at beginning of the period (in dollars per share)	$ 4.59
Granted (in dollars per share)	1.26
Forfeited (in dollars per share)	1.21
Vested (in dollars per share)	4.47
Outstanding at end of the period (in dollars per share)	$ 2.80
Market/Service Vesting Restricted Stock Units
Market / Service Vesting Restricted Stock Units
Outstanding at beginning of the period (in shares) \| shares	8,105
Granted (in shares) \| shares	4,238
Forfeited (in shares) \| shares	(254)
Vested (in shares) \| shares	(590)
Outstanding at end of the period (in shares) \| shares	11,499
Weighted-Average Grant-Date Fair Value
Outstanding at beginning of the period (in dollars per share)	$ 8.43
Granted (in dollars per share)	1.96
Forfeited (in dollars per share)	4.37
Vested (in dollars per share)	12.25
Outstanding at end of the period (in dollars per share)	4.26
Market/Service Vesting Restricted Stock Units \| Minimum
Weighted-Average Grant-Date Fair Value
Granted (in dollars per share)	$ 1.94
Vesting percentage of the awards granted (as a percent)	0.00%
Market/Service Vesting Restricted Stock Units \| Maximum
Weighted-Average Grant-Date Fair Value
Granted (in dollars per share)	$ 13.06
Vesting percentage of the awards granted (as a percent)	200.00%
Percent threshold target for grants and forfeitures (as a percent)	100.00%

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2026	Dec. 31, 2025
Statement of Financial Position [Abstract]
Preference shares, par value (in dollars per share)	$ 0.01	$ 0.01
Preference shares, authorized shares (in shares)	200,000,000	200,000,000
Preference shares, issued shares (in shares)	0	0
Common shares, par value (in dollars per share)	$ 0.01	$ 0.01
Common shares, authorized shares (in shares)	2,000,000,000	2,000,000,000
Common shares, issued shares (in shares)	638,126,969	522,590,223
Treasury stock shares (in shares)	44,263,269	44,263,269

- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References + Details

- Definition

Number of shares issued for nonredeemable preferred shares and preferred shares redeemable solely at option of issuer. Includes, but is not limited to, preferred shares issued, repurchased, and held as treasury shares. Excludes preferred shares classified as debt.

+ References + Details

Receivables (Tables)

6 Months Ended

Jun. 30, 2026

Receivables [Abstract]

Schedule of Receivables

Receivables consisted of the following:


	June 30, 2026		December 31, 2025
	(In thousands)
Joint interest billings, net	$	13,780	$	17,255
Oil and gas sales	90,369		56,700
Other current receivables	8,873		29,517
Total receivables	$	113,022	$	103,472

Long-term receivables	$	472,897	$	458,793

Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2026

Accounting Policies [Abstract]

Schedule of Cash and Cash Equivalents

Cash, Cash Equivalents and Restricted Cash


	June 30, 2026		December 31, 2025
	(In thousands)
Cash and cash equivalents	$	102,137	$	91,518

Restricted cash - current	23,505		—
Restricted cash - long-term	30,589		26,226
Total cash, cash equivalents and restricted cash in the consolidated statements of cash flows	$	156,231	$	117,744

Schedule of Oil and Gas Revenue

Oil and gas revenue is composed of the following:


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
	(In thousands)
Revenues from contracts with customers:
Ghana	$	365,880	$	212,880	$	616,032	$	365,685
Equatorial Guinea	47,464		63,196		71,951		96,878
Mauritania\|Senegal	93,596		20,239		145,862		22,936
Gulf of America	111,439		103,100		206,241		204,878
Total revenues from contracts with customers	618,379		399,415		1,040,086		690,377
Provisional sales contracts	(11,126)		(6,780)		(62,105)		(7,607)
Oil and gas revenue	$	607,253	$	392,635	$	977,981	$	682,770

Schedule of Consolidated Oil and Gas Revenue

Customers in our Gulf of America and Mauritania | Senegal business units that comprise 10% or more of our total consolidated oil and gas revenue for the three and six months ended June 30, 2026 and 2025, are shown below.


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
	(Percentage)
Customer
BP plc	77	%	18	%	62	%	19	%
Shell Trading (US) Company	18	%	4	%	20	%	5	%

Equity-based Compensation

6 Months Ended

Jun. 30, 2026

Share-Based Payment Arrangement [Abstract]

Equity-based Compensation

Restricted Stock Units

We record equity-based compensation expense equal to the fair value of share-based payments over the vesting periods of the LTIP awards. We recorded compensation expense from awards granted under our LTIP of $8.1 million and $7.3 million during the three months ended June 30, 2026 and 2025, respectively, and $14.1 million and $15.7 million during the six months ended June 30, 2026 and 2025, respectively. The total tax benefit for the three months ended June 30, 2026 and 2025 was $0.9 million and $1.2 million, respectively, and $1.9 million and $2.6 million during the six months ended June 30, 2026 and 2025, respectively. Additionally, we recorded a net tax shortfall (windfall) related to equity-based compensation of $(0.1) million and $0.3 million for the three months ended June 30, 2026 and 2025, respectively, and $7.6 million and $3.4 million during the six months ended June 30, 2026 and 2025, respectively. The fair value of awards vested during the three months ended June 30, 2026 and 2025 was $2.0 million and $0.6 million, respectively, and $5.7 million and $19.7 million during the six months ended June 30, 2026 and 2025, respectively. The Company granted restricted stock units with service vesting criteria and a combination of market and service vesting criteria under the LTIP. Substantially all of these grants vest over three years. Upon vesting, restricted stock units become issued and outstanding stock.

For restricted stock units with a combination of market and service vesting criteria, the number of common shares to be issued is determined by comparing the Company’s total shareholder return with the total shareholder return of a predetermined group of peer companies over the performance period and can vest in up to 200% of the awards granted. The grant date fair value ranged from $1.94 to $13.06 per award. The Monte Carlo simulation model utilized multiple input variables that determined the probability of satisfying the market condition stipulated in the award grant and calculated the fair value of the award. The expected volatility utilized in the model was estimated using our historical volatility and the historical volatilities of our peer companies and ranged from 58.0% to 105.0%. The risk-free interest rate was based on the U.S. treasury rate for a term commensurate with the expected life of the grant and ranged from 1.3% to 4.2%.

The following table reflects the outstanding restricted stock units as of June 30, 2026:


		Weighted-		Market / Service	Weighted-
	Service Vesting	Average		Vesting	Average
	Restricted Stock	Grant-Date		Restricted Stock	Grant-Date
	Units	Fair Value		Units	Fair Value
	(In thousands)			(In thousands)
Outstanding at December 31, 2025	5,073	$	4.59	8,105	$	8.43
Granted(1)	5,275	1.26		4,238	1.96
Forfeited(1)	(864)	1.21		(254)	4.37
Vested	(2,824)	4.47		(590)	12.25
Outstanding at June 30, 2026	6,660	$	2.80	11,499	$	4.26

__________________________________

As of June 30, 2026, total equity-based compensation to be recognized on unvested restricted stock units is $21.2 million over a weighted average period of 1.74 years. At June 30, 2026, the Company had approximately 11.9 million shares that remain available for issuance under the LTIP.

Acquisitions and Divestitures (Tables)

6 Months Ended

Jun. 30, 2026

Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]

Schedule of Major Classes of Assets and Liabilities

The following table summarizes the carrying amounts of the major classes of assets and liabilities included in the disposal group as of the date of sale:


	As of date of sale
	(In thousands)
Assets
Current assets:
Cash and cash equivalents	$	—
Receivables	—
Inventories	9,100
Prepaid expenses and other	737
Total current assets	9,837

Non-current assets:
Property and equipment, net	410,458
Total non-current assets	410,458
Total assets of disposal group	$	420,295

Liabilities
Current liabilities:
Accounts Payable	$	34,376
Accrued Liabilities	—
Total current liabilities	34,376

Long-term Liabilities
Asset retirement obligations	142,211
Deferred tax liabilities	126,092
Total long-term liabilities	268,303
Total liabilities of disposal group	$	302,679

- Definition

Tabular disclosure of information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-3

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-3A

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 102
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483474/205-20-55-102

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483475/205-20-45-11

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 103
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483474/205-20-55-103

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5C
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-5C

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480781/205-20-S99-3

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-5C

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-5B

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-4B

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-3

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-1

Reference 13: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-1

+ Details

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Shares	Additional Paid-in Capital	Accumulated Deficit	Treasury Stock
Balance at the beginning (in shares) at Dec. 31, 2024		516,159
Balance at the beginning at Dec. 31, 2024	$ 1,200,424	$ 5,162	$ 2,514,739	$ (1,082,470)	$ (237,007)
Increase (Decrease) in Shareholders' Equity
Equity-based compensation	8,362		8,362
Restricted stock units (in shares)		6,009
Restricted stock units	0	$ 60	(60)
Net (loss) income	(110,606)			(110,606)
Balance at the end (in shares) at Mar. 31, 2025		522,168
Balance at the end at Mar. 31, 2025	1,098,180	$ 5,222	2,523,041	(1,193,076)	(237,007)
Balance at the beginning (in shares) at Dec. 31, 2024		516,159
Balance at the beginning at Dec. 31, 2024	1,200,424	$ 5,162	2,514,739	(1,082,470)	(237,007)
Increase (Decrease) in Shareholders' Equity
Net (loss) income	(198,346)
Balance at the end (in shares) at Jun. 30, 2025		522,483
Balance at the end at Jun. 30, 2025	1,017,784	$ 5,225	2,530,382	(1,280,816)	(237,007)
Balance at the beginning (in shares) at Mar. 31, 2025		522,168
Balance at the beginning at Mar. 31, 2025	1,098,180	$ 5,222	2,523,041	(1,193,076)	(237,007)
Increase (Decrease) in Shareholders' Equity
Equity-based compensation	7,345		7,345
Restricted stock units (in shares)		315
Restricted stock units	0	$ 3	(3)
Tax withholdings and cash settlements on restricted stock units	(1)		(1)
Net (loss) income	(87,740)			(87,740)
Balance at the end (in shares) at Jun. 30, 2025		522,483
Balance at the end at Jun. 30, 2025	1,017,784	$ 5,225	2,530,382	(1,280,816)	(237,007)
Balance at the beginning (in shares) at Dec. 31, 2025		522,590
Balance at the beginning at Dec. 31, 2025	528,590	$ 5,226	2,542,627	(1,782,256)	(237,007)
Increase (Decrease) in Shareholders' Equity
Equity-based compensation	5,950		5,950
Restricted stock units (in shares)		2,698
Restricted stock units	0	$ 27	(27)
Public offering of common stock (in shares)		112,125
Public offering of common stock	206,143	$ 1,121	205,022
Net (loss) income	(225,574)			(225,574)
Balance at the end (in shares) at Mar. 31, 2026		637,413
Balance at the end at Mar. 31, 2026	515,109	$ 6,374	2,753,572	(2,007,830)	(237,007)
Balance at the beginning (in shares) at Dec. 31, 2025		522,590
Balance at the beginning at Dec. 31, 2025	528,590	$ 5,226	2,542,627	(1,782,256)	(237,007)
Increase (Decrease) in Shareholders' Equity
Net (loss) income	(40,799)
Balance at the end (in shares) at Jun. 30, 2026		638,127
Balance at the end at Jun. 30, 2026	704,897	$ 6,381	2,758,578	(1,823,055)	(237,007)
Balance at the beginning (in shares) at Mar. 31, 2026		637,413
Balance at the beginning at Mar. 31, 2026	515,109	$ 6,374	2,753,572	(2,007,830)	(237,007)
Increase (Decrease) in Shareholders' Equity
Equity-based compensation	5,018		5,018
Restricted stock units (in shares)		714
Restricted stock units	0	$ 7	(7)
Tax withholdings and cash settlements on restricted stock units	(5)		(5)
Net (loss) income	184,775			184,775
Balance at the end (in shares) at Jun. 30, 2026		638,127
Balance at the end at Jun. 30, 2026	$ 704,897	$ 6,381	$ 2,758,578	$ (1,823,055)	$ (237,007)

Commitments and Contingencies (Details) MT in Thousands, MMBTU in Thousands, $ in Millions	1 Months Ended	6 Months Ended
	Feb. 28, 2026 USD ($)	Jun. 30, 2026 USD ($) well MMBTU MT	Dec. 31, 2025 USD ($)
Commitments And Contigencies [Line Items]
Estimated decommissioning costs		$ 111.0
Commitments estimated period		14 years
Supply commitment, volume of LNG \| MMBTU		127,951
Supply commitment, volume of LNG supplied per annum \| MT		2,450
TEN FPSO
Commitments And Contigencies [Line Items]
Gross purchase price	$ 205.0
Ghana
Commitments And Contigencies [Line Items]
Number of development wells \| well		10
Gulf of America \| Bureau Of Ocean Energy Management and Other Third Parties \| Surety Bond
Commitments And Contigencies [Line Items]
Required performance bonds		$ 150.5	$ 151.6

Derivative Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2026

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Oil Derivative Contracts and Interest Rate Swap


				Weighted Average Price per Bbl
				Net Deferred
				Premium
				Payable/		Sold
Term	Type of Contract	Index	MBbl	(Receivable)	Swap	Put	Floor	Ceiling
2026:
Jul - Dec	Three-way collars	Dated Brent	1,000	—	—	50.00	60.00	75.51
Jul - Dec	Swaps(1)	Dated Brent	500	—	72.46	—	—	100.00
Jul - Dec	Swaps(1)	Dated Brent	1,000	—	69.70	55.00	—	—
Jul - Dec	Swaps(1)	NYMEX WTI	750	—	64.83	50.00	—	—
2027:
Jan - Dec	Three-way collars	Dated Brent	2,000	0.40	—	47.50	60.00	75.00
Jan - Jun	Three-way collars	Dated Brent	2,000	0.03	—	55.00	70.00	85.00
Jan - Dec	Three-way collars	NYMEX WTI	1,000	0.50	—	55.00	70.00	90.00

__________________________________

(1)Includes option contracts sold to counterparties to enhance Swaps.

Schedule of Derivative Instruments by Balance Sheet Location


		Estimated Fair Value
		Asset (Liability)
Type of Contract	Balance Sheet Location	June 30, 2026		December 31, 2025
		(In thousands)
Derivatives not designated as hedging instruments:
Derivative assets:
Commodity	Derivatives assets—current	$	459	$	47,816
Provisional sales contracts	Receivables: Oil and gas sales	857		—

Commodity	Derivatives assets—long-term	2,335		2,681
Derivative liabilities:
Commodity	Derivatives liabilities—current	(11,633)		—


Commodity	Derivatives liabilities—long-term	(5,129)		—

Total derivatives not designated as hedging instruments		$	(13,111)	$	50,497

Schedule of Derivative Instruments by Location of Gain/(Loss)


		Amount of Gain/(Loss)				Amount of Gain/(Loss)
		Three Months Ended				Six Months Ended
		June 30,				June 30,
Type of Contract	Location of Gain/(Loss)	2026		2025		2026		2025
		(In thousands)
Derivatives not designated as hedging instruments:
Provisional sales contracts	Oil and gas revenue	$	(11,126)	$	(6,780)	$	(62,105)	$	(7,607)
Commodity	Derivatives, net	51,809		21,566		(200,187)		14,834
Interest rate	Interest expense	—		683		—		656
Total derivatives not designated as hedging instruments		$	40,683	$	15,469	$	(262,292)	$	7,883

Equity-based Compensation - Narrative (Details) - LTIP - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense recognized	$ 8.1	$ 7.3	$ 14.1	$ 15.7
Tax benefit	0.9	1.2	1.9	2.6
Net tax (windfall) shortfall related to equity-based compensation	(0.1)	0.3	7.6	3.4
Fair value of awards vested	$ 2.0	$ 0.6	$ 5.7	$ 19.7
Vesting period (in years)			3 years
Number of shares remaining available for grant (in shares)	11.9		11.9
Market/Service Vesting Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value of awards granted (in dollars per share)			$ 1.96
Market/Service Vesting Restricted Stock Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of the awards granted (as a percent)			200.00%
Grant date fair value of awards granted (in dollars per share)			$ 13.06
Expected volatility			105.00%
Risk-free interest rate (as a percent)			4.20%
Market/Service Vesting Restricted Stock Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of the awards granted (as a percent)			0.00%
Grant date fair value of awards granted (in dollars per share)			$ 1.94
Expected volatility			58.00%
Risk-free interest rate (as a percent)			1.30%
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense not yet recognized	$ 21.2		$ 21.2
Weighted average period over which compensation expense is to be recognized (in years)			1 year 8 months 26 days

Debt - Facility (Details)		1 Months Ended	3 Months Ended	6 Months Ended
Debt - Facility (Details)	Mar. 31, 2026 USD ($)	Apr. 30, 2024	Mar. 31, 2026 USD ($)	Jun. 30, 2026 USD ($)	Oct. 01, 2026	Sep. 30, 2026	Apr. 30, 2026 USD ($)	Feb. 28, 2026 assessment	Dec. 31, 2025 USD ($)	Sep. 30, 2025	Jul. 31, 2025 assessment	Dec. 31, 2024	Sep. 30, 2024	Mar. 31, 2024	Oct. 31, 2021	Mar. 31, 2021
Debt Instrument [Line Items]
Total long-term debt				$ 2,719,676,000					$ 3,100,274,000
Facility
Debt Instrument [Line Items]
Debt cover ratio	2.50	2.50	2.50
Restricted cash required			$ 23,500,000
Debt service reserve account	$ 23,500,000			23,500,000
Number of covenant assessment dates \| assessment								2			2
Facility \| Facility, July 2025 Amendment
Debt Instrument [Line Items]
Debt cover ratio	4.25		4.25							4.0
Facility \| Facility, February 2026 Amendment, Excluding Mauritania And Senegal Business Units
Debt Instrument [Line Items]
Debt cover ratio	4.5		4.5
Facility \| Forecast \| Facility, July 2025 Amendment
Debt Instrument [Line Items]
Debt cover ratio						3.50
Facility \| Forecast \| Facility, February 2026 Amendment
Debt Instrument [Line Items]
Debt cover ratio					3.5	4.25
Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity				1,200,000,000			$ 1,250,000,000
Total long-term debt				800,000,000
Undrawn availability				440,000,000
Interval period for payment of interest (in months)		6 months
Commitment fees percentage		30.00%
Unavailable capacity commitment fee percentage		20.00%
Facility \| Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Applicable margin (as a percent)		4.00%
Facility \| Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Applicable margin (as a percent)		5.50%
Facility \| Letter of Credit
Debt Instrument [Line Items]
Letters of credit issued				0
Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Total long-term debt				$ 773,000,000					1,200,000,000
Facility Interest or Senior Notes
Debt Instrument [Line Items]
Period for contractual future interest payments				6 months
7.750% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Total long-term debt				$ 99,973,000					350,000,000
Interest rate (as a percent)															7.75%
7.500% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Total long-term debt				400,274,000					400,274,000
Interest rate (as a percent)																7.50%
8.750% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Total long-term debt				500,000,000					500,000,000
Interest rate (as a percent)													8.75%
3.125% Convertible Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Total long-term debt				$ 400,000,000					$ 400,000,000
Interest rate (as a percent)				3.125%					3.125%			3.125%		3.125%

Fair Value Measurements - Schedule of Investments in Debt Securities Held by Decommissioning Trust Fund (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Fair Value Measurements
Purchases	$ 209	$ 198	$ 12,051	$ 12,406
Net Proceeds	149	25	182	(579)
Unrealized Gain (Loss)	(18)	22	(106)	131
Debt securities held in decommissioning trust fund
Fair Value Measurements
Purchases	209	198	12,051	12,406
Net Proceeds	0	0	0	0
Unrealized Gain (Loss)	(18)	22	(106)	131
Cash and cash equivalents
Fair Value Measurements
Purchases	0	0	0	0
Net Proceeds	(7)	2	1	(745)
Unrealized Gain (Loss)	0	0	0	0
Other
Fair Value Measurements
Purchases	0	0	0	0
Net Proceeds	156	23	181	166
Unrealized Gain (Loss)	$ 0	$ 0	$ 0	$ 0

Commitments and Contingencies	6 Months Ended
Commitments and Contingencies	Jun. 30, 2026
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies From time to time, we are involved in litigation, regulatory examinations and administrative proceedings primarily arising in the ordinary course of our business in jurisdictions in which we do business. Although the outcome of these matters cannot be predicted with certainty, management believes that the likelihood of an unfavorable outcome having a material impact is neither reasonably possible nor probable of occurring. As of June 30, 2026, we have a commitment to drill a minimum of ten development wells under the amended Jubilee plan of development as part of the license extensions of WCTP and DT Petroleum Agreements in Ghana. In April 2024, a decommissioning trust agreement with the Jubilee unit partners to cash fund future retirement costs associated with the Jubilee Field was finalized. The operator currently estimates the total remaining commitment to be approximately $111.0 million as of June 30, 2026, net to Kosmos, which will be funded annually by Kosmos over an estimated fourteen year period. Performance Obligations As of June 30, 2026 and December 31, 2025, the Company had performance and supplemental bonds totaling $150.5 million and $151.6 million, respectively, related to bonding requirements stipulated by the BOEM and other third parties for anticipated plugging and abandonment costs of certain wells and the removal of certain facilities in our Gulf of America fields. Once the Tortue Phase 1 SPA Commercial Operations Date was achieved in February 2026, we have a commitment to our buyer under the Tortue Phase 1 SPA, BP Gas Marketing Limited, to deliver our proportionate share of a minimum annual contract quantity of LNG of 127,951,000 MMBtu, which is equivalent to approximately 2.45 million tonnes per annum, subject to certain downward adjustments by the sellers. Under certain circumstances, in the event the annual quantities provided are lower than the minimum annual contract quantity, Kosmos may be obligated to credit or pay a portion of the Contract Price to BP Gas Marketing Limited for the shortfall volumes. In February 2026, Tullow, as Operator of the TEN partnership, executed the final Sale and Purchase Agreement enabling the partnership to acquire the TEN FPSO from MODEC, Inc. at the end of its current lease in 2027 for a gross purchase price of $205.0 million. We have a commitment to Tullow for our proportionate share of the gross purchase price.