Century Aluminum is a producer of primary aluminum, which trades as a global commodity, and owns a 55% interest in a bauxite mining and alumina refinery joint venture. We are organized as a holding company, with our operating primary aluminum smelters and our bauxite mining and alumina refinery joint venture owned by separate subsidiaries.

Throughout this Form 10-Q, and unless expressly stated otherwise or as the context otherwise requires, "Century Aluminum", "Century", "the Company", "we", "us", "our" and "ours" refer to Century Aluminum Company and its consolidated subsidiaries.

The accompanying unaudited interim consolidated financial statements of Century Aluminum Company should be read in conjunction with the audited consolidated financial statements for the year ended December 31, 2025. In management’s opinion, the unaudited interim consolidated financial statements reflect all adjustments, which are of a normal and recurring nature, that are necessary for a fair presentation of financial results for the interim periods presented. Operating results for the first six months of 2026 are not necessarily indicative of the results that may be expected for the year ending December 31, 2026.

Our consolidated financial statements include the consolidated results of the Jamalco joint venture ("Jamalco"), an unincorporated joint venture between Clarendon Alumina Production Limited ("CAP") and General Alumina Jamaica Limited ("GAJL"), an indirect, wholly-owned subsidiary of the Company through General Alumina Holdings Limited ("GAHL"). CAP's interest in the joint venture is reflected as noncontrolling interest on the accompanying Consolidated Balance Sheets.

Certain amounts in the prior period financial statements have been reclassified to conform to the presentation of the current period financial statements. These immaterial reclassifications had no effect on the previously reported net income or net cash flows.

As noted in the Company's Form 10-K for the fiscal year ending December 31, 2025, as filed with the SEC on March 3, 2026, the Company has restated the comparative financial statements including the Consolidated Statement of Operations, Consolidated Balance Sheets, and Consolidated Statement of Stockholders' Equity as of and for the three and six months ended June 30, 2025, and applicable footnotes. The restatement reflects a change related to the consolidation of the Company's Jamalco joint venture whereby the Company previously used the proportionate method of consolidation for certain of Jamalco's net assets versus the full consolidation method. The change in consolidation method did not have any impact on our net income attributable to Century stockholders for the periods that were restated.


	Three months ended June 30, 2025
	As Previously Reported		Restatement Impacts		As Restated
Cost of Goods Sold	$	591.9	$	2.6	$	594.5
Gross profit	36.2		(2.6)		33.6
Operating income	20.7		(2.6)		18.1
Loss before income taxes	(10.4)		(2.6)		(13.0)

Net loss	(9.1)		(2.6)		(11.7)
Net loss attributable to noncontrolling interests	(4.5)		(2.6)		(7.1)
Net loss attributable to Century stockholders	(4.6)		—		(4.6)
Less: Net income allocated to participating securities	—		—		—
Net loss allocated to common stockholders	$	(4.6)	$	—	$	(4.6)


	June 30, 2025
	As Previously Reported		Restatement Impacts		As Restated
ASSETS
Non-trade receivables	$	—	$	17.1	$	17.1
Total current assets	790.3		17.1		807.4
Property, plant and equipment - net	975.6		175.2		1,150.8
Other assets	69.6		1.0		70.6
TOTAL	$	1,949.0	$	193.3	$	2,142.3
LIABILITIES AND SHAREHOLDERS’ EQUITY
LIABILITIES:
Accrued compensation and benefits	$	44.2	$	1.0	$	45.2
Non-trade payables	7.7		(7.7)		—
Accrued and other current liabilities	44.9		3.1		48.0
Total current liabilities	451.1		(3.6)		447.5
Accrued benefits costs - less current portion	127.8		14.5		142.3
Asset retirement obligations - less current portion	63.2		19.3		82.5
Total noncurrent liabilities	813.6		33.8		847.4

SHAREHOLDERS’ EQUITY:
Noncontrolling interests	(40.1)		163.1		123.0
Total equity	684.3		163.1		847.4
TOTAL	$	1,949.0	$	193.3	$	2,142.3


Three months ended June 30, 2025
(As Previously Reported)	Noncontrolling interest		Total equity
Balance, March 31, 2025	$	(35.6)	$	690.7
Net income (loss)	(4.5)		(9.1)
Other comprehensive income (loss)	—		1.5
Share-based compensation	—		1.2
Contributions from noncontrolling interest	—		—
Balance, June 30, 2025	$	(40.1)	$	684.3

(Restatement Impacts)
Net income (loss)	$	(2.6)	$	(2.6)
Contributions from noncontrolling interest	18.6		18.6

(As Restated)
Balance, March 31, 2025	111.5		837.8
Net income (loss)	(7.1)		(11.7)
Other comprehensive income (loss)	—		1.5
Share-based compensation	—		1.2
Contributions from noncontrolling interest	18.6		18.6
Balance, June 30, 2025	$	123.0	$	847.4

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, that requires disclosure of the amounts of purchases of inventory, employee compensation, depreciation, and intangible asset amortization included in each relevant expense line item on the income statement. The standard also requires a qualitative description of other amounts included in each relevant expense line item on the income statement that are not separately disclosed. In addition, entities are required to disclose the nature and amount of selling expenses. The new standard is effective for fiscal years beginning after December 15, 2026, and interim periods beginning after December 15, 2027. Early adoption is permitted. We do not expect any impact to the consolidated financial statements, but the standard will require certain additional disclosures. The Company plans to adopt this guidance for the annual period ending December 31, 2027.

In December 2025, the FASB issued ASU 2025-10, Government Grants (Topic 832): Accounting for Government Grants Received by Business Entities, which adds guidance on the recognition, measurement and presentation of government grants. The new standard is effective for fiscal years beginning after December 15, 2028. Early adoption is permitted. The Company has previously analogized to IAS 20, Accounting for Government Grants and Disclosure of Government Assistance, to account for refundable tax credits as an income grant. The Company's policy on income grants under IAS 20 aligns with the updated guidance, and the Company does not expect a material effect on its consolidated financial statements upon adoption.

In May 2026, the FASB issued ASU 2026-02, Environmental Credits and Environmental Credit Obligations (Topic 818), which introduces a comprehensive model that establishes recognition, measurement, presentation, and disclosure requirements for environmental credits and, when applicable, compliance obligations that may be settled by using environmental credits. The new standard is effective for fiscal years beginning after December 15, 2027, and interim reporting periods within those annual reporting periods, applied retrospectively by making a cumulative-effect adjustment to the opening balance of retained earnings. Early adoption is permitted. If an entity adopts the standard in an interim reporting period, it must adopt the guidance as of the

beginning of the annual reporting period that includes that interim reporting period. The Company's policy for environmental credit accounting aligns with the standard and there will be no material impact to the consolidated financial statements. The standard will require certain additional disclosures.