CENTURY ALUMINUM CO

Condensed Notes to the Consolidated Financial Statements

Nine months ended September 30, 2026 and 2025

1. General

Description of Business

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.

Basis of Presentation

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 nine 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.

Restatement

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 nine months ended September 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.

The following tables present a summary of the effects of the correction of the Company’s previously issued consolidated financial statements as of and for the three months ended September 30, 2025.

The effects of the corrections described above to the Company's consolidated statements of operations are shown below.

The effects of the corrections described above to the Company's consolidated balance statements are shown below.

The effects of the corrections described above to the Company's consolidated statements of shareholders' equity are shown below.

Recent Accounting Pronouncements

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.

2. Related Party Transactions

The significant related party transactions occurring during the three and nine months ended September 30, 2026 and 2025 are described below. All of our related party transactions are subject to the Company's Related Party Transaction Policy and are required to be made on an arm's length basis and on terms that are fair and reasonable to the Company and substantially the same as would apply if the other party was not a related party. We believe all of our transactions with related parties are at prices that approximate market.

Glencore Ownership

As of September 30, 2026, Glencore plc and its affiliates (together "Glencore") beneficially owned 30.0% of Century’s outstanding common stock. Century and Glencore enter into various transactions from time to time, such as the purchase and sale of primary aluminum, alumina and other raw materials; tolling agreements; forward financial contracts and borrowing and other debt transactions.

Sales to Glencore

For thethree months ended September 30, 2026 and 2025, we derived approximately 51.1% and 50.6%, respectively, of our consolidated net sales from Glencore. For thenine months ended September 30, 2026 and 2025, we derived approximately 47.8% and 56.3%, respectively, of our consolidated net sales from Glencore.

Glencore purchases aluminum produced at our U.S. smelters at prices based on the London Metal Exchange ("LME") plus the Midwest regional delivery premium plus any additional market-based product premiums. Glencore purchases aluminum produced at our Grundartangi, Iceland smelter at prices based on the LME plus the European Duty Paid premium plus any additional market-based product premiums.

We have entered into agreements with Glencore pursuant to which we sell certain amounts of alumina at market-based prices. For thethree and nine months ended September 30, 2026, the Company recognized $44.7 million and $156.2 million, respectively, of revenue related to alumina sales to Glencore. For thethree and nine months ended September 30, 2025, the Company recognized$34.8 million and $161.2 million, respectively, of revenue related to alumina sales to Glencore.

Purchases from Glencore

We purchase a portion of our alumina and certain other raw material requirements from Glencore. Alumina purchases from Glencore during the three and nine months ended September 30, 2026 and 2025 were priced based on aluminum indices.

Summary

A summary of the aforementioned significant related party sales and purchases is as follows:

Vlissingen Credit Facility

On December 9, 2022, Vlissingen entered into a Facility Agreement with Glencore International AG, which was amended and extended on October 1, 2024 and on November 4, 2026 (as amended, the “Vlissingen Credit Facility”). The availability period for borrowings under the Vlissingen Credit Facility ends on December 2, 2028. Under the Vlissingen Credit Facility, Vlissingen may borrow from time to time up to $90.0 million in one or more loans at a variable interest rate equal to the 1-month SOFR rate plus 3.687 percentage points. The interest rate is subject to an absolute maximum level of 9.00% and an absolute minimum level of 7.00% through December 1, 2026. Beginning on December 2, 2026, the interest rate is subject to an absolute maximum level of 10.00% and an absolute minimum level of 8.00%. As of September 30, 2026, there wereno outstanding borrowings under the Vlissingen Credit Facility. See Note 12. Debt for additional information. Any borrowings under the Vlissingen Credit Facility are expected to be used for general corporate and working capital purposes of Century and its subsidiaries.

3. Revenue

We enter into contracts to sell mainly primary aluminum to our customers. Revenue is recognized when our performance obligations with our customers are satisfied. Our obligations under the contracts are satisfied when we transfer control of our primary aluminum to our customers, which is generally upon shipment or delivery to customer directed locations. The amount of consideration we receive, thus the revenue we recognize, is a function of the volume delivered and the market price of primary aluminum, which is based on the LME, plus regional premiums and any value-added product premiums. For alumina, consideration is based on the alumina pricing index, plus Atlantic differential.

The payment terms and conditions in our contracts vary and are not significant to our revenue. We complete an appropriate credit evaluation for each customer at contract inception. Customer payments are due in arrears and are recognized as Accounts receivable - net and Due from affiliates in our Consolidated Balance Sheets.

In connection with our sales agreements with certain customers, including Glencore, we invoice the customer prior to physical shipment of goods for a majority of production generated from each of our U.S. domestic smelters. For those sales, revenue is recognized only when the customer has specifically requested such treatment and has made a commitment to purchase the product. The goods must be complete, ready for shipment and separated from other inventory with control over the goods passing to the customer. We must retain no further performance obligations.

Contract liabilities are recorded when cash payments are received or due in advance of performance. Amounts recognized in Due to affiliates was $12.0 million and $31.2 million, as of September 30, 2026 and December 31, 2025, respectively.

The table below shows the amount of net sales to external customers for each of the Company's product categories which accounted for 10% or more of consolidated net sales in either period for the three and nine months ended September 30, 2026 and 2025.

Our net sales are attributed to geographic area based on the location of the selling entity. Included in the consolidated financial statements are the following amounts related to geographic locations:

(1)Includes sales of primary aluminum, scrap aluminum and alumina, and purchased aluminum and alumina.

4. Sale of Hawesville

In August 2022, we fully curtailed production at the Hawesville, Kentucky facility ("Hawesville"). On February 2, 2026, we completed the sale of the facility to an affiliate of Terawulf, Inc. for $200.0 million in cash and a 6.8% non-dilutive minority equity interest in Raylan Data Holdings LLC (the "Minority Interest"), a joint venture that intends to develop and own a high-performance computing/artificial intelligence data center on the site. We also have the right to require the majority holder to purchase the Minority Interest for $300.0 million starting on the first anniversary of the data center’s commencement of the data center's operations (the "Put Option"). The Minority Interest and Put Option were measured at fair value at the acquisition date as one unit of account and is accounted for using the equity method. The value of the equity method investment is recorded within Other assets on the Consolidated Balance Sheets. See Note 10. Fair Value Measurements for additional information on the valuation of the Minority Interest and Put Option. We recognized a gain of $287.9 million in connection with the sale.

The major classes of assets and liabilities that were sold are as follows:

As a result of the sale, in accordance with a debt covenant, we set aside part of the cash proceeds restricted for use only on capital expenditures or otherwise invested in our business, of which $32.4 million remains on our Consolidated Balance Sheets at September 30, 2026.

5. Income Taxes

For the three months ended September 30, 2026 and 2025, we recorded an income tax expense of $11.6 million and an income tax benefit of $1.1 million, respectively. For the nine months ended September 30, 2026 and 2025, we recorded income tax expense of $25.5 million and an income tax benefit of $0.8 million, respectively. The change is primarily due to changes in pretax income amounts and jurisdictional mix on a year over year basis.

Our income tax expense or benefit for interim periods is determined using an estimate of our annual effective tax rate ("AETR"), adjusted for discrete items. In February 2026, the Company completed the sale of Hawesville. The sale was determined to be a discrete item that is not part of the Company’s ordinary operations and, accordingly, the related tax effects were excluded from the computation of the estimated AETR. The application of the accounting requirements for income taxes in interim periods, after consideration of our valuation allowance on domestic losses, causes a significant variation in the typical relationship between income tax expense/benefit and pretax accounting income/loss as reported on the Consolidated Statements of Operations.

The Company evaluates the realizability of its deferred tax assets on a quarterly basis using all available evidence, both positive and negative. The realization of deferred tax assets is dependent on the Company's ability to generate sufficient future taxable income during periods prior to the expiration of tax attributes to fully utilize these assets. As of September 30, 2026, all of Century's U.S. and certain foreign deferred tax assets, net of deferred tax liabilities, continue to be subject to a full valuation allowance. Based on the Company’s assessment of current and anticipated future earnings, it is reasonably possible that sufficient positive evidence of sustained U.S. profitability may become available within the next 12 months to reach a conclusion that the U.S. valuation allowance will no longer be needed. Release of the valuation allowance would result in the recognition of certain deferred tax assets and a corresponding decrease to income tax expense in the period the release is recorded. The timing and amount of any valuation allowance release could vary based on the level of profitability that the Company is actually able to achieve.

Section 45X of the Inflation Reduction Act of 2022 ("IRA") contains a production tax credit equal to 10% of certain eligible production costs, including, without limitation, labor, energy, depreciation and amortization and overhead expenses. On October 24, 2024, the U.S. Department of the Treasury and the Internal Revenue Service issued final regulations on the production tax credit requirements under Internal Revenue Code Section 45X (the "IRA Regulations"). The IRA Regulations provide guidance on rules that taxpayers must satisfy to qualify for the IRA Section 45X tax credit. For the three months ended September 30, 2026 and 2025, the Company recognized a reduction of $26.3 million and $24.7 million in Cost of goods sold and a reduction of $0.9 million and $0.7 million in Selling, general and administrative expenses, respectively, within the Consolidated Statements of Operations. For the nine months ended September 30, 2026 and 2025, the Company recognized a reduction of $77.6 million and $66.5 million in Cost of goods sold and a reduction of $2.2 million and $2.0 million in Selling, general and administrative expenses, respectively, within the Consolidated Statements of Operations.

6. Earnings Per Share

Basic earnings per share ("EPS") amounts are calculated by dividing earnings available to common stockholders by the weighted average number of common shares outstanding. Diluted EPS is calculated by dividing net income attributable to common shareholders by the weighted average number of common and dilutive common equivalent shares outstanding during the period. Beginning in 2026, due to the previous conversion of all preferred stock to common, dilutive common equivalent shares are calculated using the treasury stock and if-converted methods. In prior periods, dilutive common equivalent shares were calculated using the more dilutive of either the two-class method or the treasury stock and if-converted methods.

The following table shows the basic and diluted earnings per share:

(1)In periods when we report a net loss, all share-based compensation awards, convertible preferred shares and convertible senior notes are excluded from the calculation of diluted weighted average shares outstanding because of their anti-dilutive effect on earnings (loss) per share.

7. Accumulated Other Comprehensive Loss ("AOCL")

(1)The allocation of the income tax effect to the components of other comprehensive loss is as follows:

The following table summarizes the changes in the accumulated balances for each component of AOCL:

Reclassifications out of AOCL were included in the Consolidated Statements of Operations as follows:

8. Components of Net Periodic Benefit Cost

9. Inventories

Inventories consist of the following:

Inventories are stated at the lower of cost or net realizable value ("NRV") using the first-in, first-out or the weighted average cost method.

10. Fair Value Measurements

We measure and classify certain of our assets and liabilities at fair value in accordance with the hierarchy as defined by the Fair Value Measurement Topic of the FASB ASC. The fair value hierarchy provides transparency regarding the inputs we use to measure fair value. We categorize each fair value measurement in its entirety into the following three levels, based on the lowest level input that is significant to the entire measurement:

•Level 1 Inputs - quoted prices (unadjusted) in active markets for identical assets or liabilities that we can access at the measurement date.

•Level 2 Inputs - inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly.

•Level 3 Inputs - unobservable inputs for the asset or liability.

(1)Trust assets are currently invested in money market funds. These trust assets are held to fund the non-qualified supplemental executive pension benefit obligations for certain of our officers.

The following section describes the valuation techniques or inputs for fair value measurements categorized within Level 2 of the fair value hierarchy:

When valuing Level 3 assets and liabilities, we use certain significant unobservable inputs. Management incorporates various inputs and assumptions including forward commodity prices, commodity price volatility and macroeconomic conditions, including interest rates and discount rates. Our estimates of significant unobservable inputs are ultimately based on our estimates of risks that market participants would consider when valuing our assets and liabilities.

During the three and nine months ended September 30, 2026 and 2025, there wereno Level 3 assets and liabilities measured at fair value on a recurring basis.

We measured the Minority Interest and the Put Option as a single unit of account at fair value as of February 2, 2026, the date of acquisition. The investment is categorized within Level 3 of the fair value hierarchy and was valued at $97.0 million using a sales comparison approach and a probability-weighted scenario approach incorporating a Black-Scholes option pricing model. The valuation considered multiple scenarios based on the timing of successful commencement of the data center’s operations, as well as a scenario in which the conditions to exercise the Put Option are not met. See Note 4. Sale of Hawesville for additional information on the acquisition of the Minority Interest and Put Option.

The following table describes the significant unobservable inputs used in the valuation.

11. Derivatives

As of September 30, 2026, we had an open position of 71,800 tonnes related to LME forward financial sales contracts to fix the forward LME aluminum price. These contracts are expected to settle monthly through December 2027. We also had an open position of 141,700 tonnes related to MWP forward financial sales contracts to fix the forward MWP price. These contracts are expected to settle monthly through December 2028. We also enter into financial contracts with various counterparties to offset fixed price sales arrangements with certain of our customers ("fixed for floating swaps") to remain exposed to the LME and MWP aluminum prices. As of September 30, 2026, we had no tonnes open related to fixed for floating swaps.

We have entered into financial contracts to hedge a portion of our Jamalco fuel cost exposure ("HFO price swaps"). The volume of heavy fuel oil ("HFO") consumed at Jamalco is measured per barrel and as of September 30, 2026, we had an open position of 5,000 barrels. The HFO price swaps settled in October 2026.

We have entered into financial contracts to fix a portion of our exposure to the Indiana Hub power market at our Sebree plant ("Indiana Hub power price swaps"). As of September 30, 2026, we had an open position of 917,040 MWh. The Indiana Hub power price swaps are expected to settle monthly through December 2027.

Our agreements with derivative counterparties contain certain provisions requiring collateral to be posted in the event the market value of our position exceeds the margin threshold limit of our master agreement with the counterparty. As of September 30, 2026 and December 31, 2025, the Company hadno recorded restricted cash as collateral related to open derivative contracts under the master arrangements with our counterparties.

The following tables set forth the Company's derivative assets and liabilities that were accounted for at fair value and not designated as cash flow hedges as of September 30, 2026 and December 31, 2025, respectively:

(1)Commodity contracts reflect our outstanding LME and MWP forward financial sales contracts, Indiana Hub power price swaps, fixed for floating swaps, and HFO price swaps.

The following table summarizes the net gain (loss) on forward and derivative contracts:

12. Debt

(1)The IRBs were classified as current liabilities because they were remarketed weekly and could have been required to be repaid upon demand if there is a failed remarketing.

(2)We incur interest at a base rate plus applicable margin as defined within the agreement. The interest rate at September 30, 2026 was 7.50%.

(3)We incur interest at a base rate plus applicable margin as defined within the agreement. The interest rate at September 30, 2026 was 7.11%.

6.875% Senior Secured Notes due 2032

General. On July 22, 2025, we issued $400.0 million in aggregate principal amount of 6.875% of senior secured notes (the "2032 Notes"). We received proceeds of $393.7 million after payment of certain financing fees and related expenses.

Interest Rate. The 2032 Notes bear interest semi-annually in arrears on February 1 and August 1 of each year, beginning on February 1, 2026, at a rate of 6.875% in cash.

Maturity. The 2032 Notes will mature on August 1, 2032, unless earlier repurchased or redeemed.

Seniority. The 2032 Notes are senior secured obligations of Century, ranking equally in right of payment with all existing and future senior indebtedness of Century, but effectively senior to unsecured debt to the extent of the value of collateral.

Guaranty. Our obligations under the 2032 Notes are guaranteed by all of our existing and future domestic restricted subsidiaries (the “Guarantor Subsidiaries”), except for foreign owned holding companies, any domestic restricted subsidiary that owns no assets other than equity interests or other investments in foreign subsidiaries and certain immaterial subsidiaries, which guaranty shall in each case be a senior secured obligation of such Guarantor Subsidiaries, ranking equally in right of payment with all existing and future senior indebtedness of such Guarantor Subsidiaries but effectively senior to unsecured debt to the extent of the value of collateral.

Collateral. Our obligations under the 2032 Notes and the Guarantor Subsidiaries' obligations under the guarantees are secured by a pledge of and lien on (subject to certain exceptions):

(i) all of our and the Guarantor Subsidiaries' property, plant and equipment (other than certain excluded property);

(ii) all equity interests in subsidiaries directly owned by Century or any Guarantor Subsidiaries; and

(iii) proceeds of the foregoing.

Under certain circumstances, the indenture and the security documents governing the 2032 Notes will permit us and the Guarantors to incur additional debt that also may be secured by liens on the collateral that are equal to or have priority over the liens securing the 2032 Notes. The collateral agent for the 2032 Notes will agree with the collateral agent for the other debt holders and us under such circumstances to enter into an intercreditor agreement that will cause the liens securing the 2032 Notes to be contractually subordinated to the liens securing such additional debt.

Redemption Rights. Prior to August 1, 2028, we may redeem the 2032 Notes, in whole or in part, at a redemption price equal to 100.00% of the principal amount plus a make-whole premium and accrued and unpaid interest, and if redeemed during thetwelve-month period beginning on August 1 of the years indicated below, at the following redemption prices plus accrued and unpaid interest:

Upon a change of control (as defined in the indenture governing the 2032 Notes), we will be required to make an offer to purchase the 2032 Notes at a purchase price equal to 101% of the outstanding principal amount of the 2032 Notes on the date of the purchase, plus accrued and unpaid interest to, but not including, the date of purchase.

Covenants. The indenture governing the 2032 Notes contains customary covenants which may limit our ability, and the ability of certain of our subsidiaries, to: (i) incur additional debt; (ii) incur additional liens; (iii) pay dividends or make distributions in respect of capital stock; (iv) purchase or redeem capital stock; (v) make investments or certain other restricted payments; (vi) sell assets; (vii) issue or sell stock of certain subsidiaries; (viii) enter into transactions with shareholders or affiliates; and (ix) effect a consolidation or merger.

As of September 30, 2026, the total estimated fair value of the 2032 Notes was $397.7 million. Although we use quoted market prices for identical debt instruments, the markets on which they trade are not considered to be active and are therefore considered Level 2 fair value measurements.

2.75% Convertible Notes due 2028

General. On April 9, 2021, we completed a private offering of $86.3 million aggregate principal amount of convertible senior notes 2028 (the "Convertible Notes"). The Convertible Notes were issued at a price of 100% of their aggregate principal amount. We received proceeds of $83.7 million, after payment of certain financing fees and related expenses.

The initial conversion rate for the Convertible Notes is 53.3547 shares of the Company's common stock per $1,000 principal amount of Convertible Notes, which is equivalent to an initial conversion price of approximately $18.74 per share of the Company's common stock. The conversion rate and conversion price are subject to customary adjustments under certain circumstances in accordance with the terms of the indenture. As of September 30, 2026, the conversion rate remains unchanged.

Interest Rate. The Convertible Notes bear interest semi-annually in arrears on May 1 and November 1 of each year at a rate of 2.75% per annum in cash.

Maturity. The Convertible Notes will mature on May 1, 2028, unless earlier converted, repurchased, or redeemed.

Seniority. The Convertible Notes are the Company’s senior unsecured obligations and rank senior in right of payment to any of the Company’s indebtedness that is expressly subordinated in right of payment to the Convertible Notes; equal in right of payment to any of the Company’s unsecured indebtedness that is not so subordinated; effectively junior in right of payment to any of the Company’s senior secured indebtedness to the extent of the value of the assets securing such indebtedness; and structurally junior to all indebtedness and other liabilities (including trade payables) of the Company’s subsidiaries.

Redemption Rights. On or after May 6, 2025, we may redeem for cash all or part of the Convertible Notes at our option if the last reported sale price of our common stock has been at least 130% of the conversion price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading-day period (including the last trading day of such period) ending on and including the trading day immediately preceding the date on which we provide notice of redemption, at a redemption price equal to 100% of the principal amount of the Convertible Notes to be redeemed, plus accrued and unpaid interest.

Upon conversion, we may satisfy our conversion obligation by paying or delivering, as applicable, cash, shares of our common stock or a combination of cash and shares of our common stock, at our election, based on the applicable conversion rate. In addition, if certain corporate events that constitute a make-whole fundamental change (as defined in the indenture) occur, then the conversion rate will, in certain circumstances, be increased for a specified period of time. Additionally, in the event of a corporate event constituting a fundamental change (as defined in the indenture), holders of the Convertible Notes may require us to repurchase all or a portion of their Convertible Notes at a repurchase price equal to 100% of the principal amount of the Convertible Notes being repurchased, plus accrued and unpaid interest to, but excluding, the date of the fundamental change repurchase.

As of September 30, 2026, the if-converted value of the Convertible Notes exceeded the outstanding principal amount by$79.3 million.

Fair Value. As of September 30, 2026, the total estimated fair value of the Convertible Notes was$167.0 million. Although we use quoted market prices for identical debt instruments, the markets on which they trade are not considered to be active and are therefore considered Level 2 fair value measurements.

U.S. Revolving Credit Facility

General. We and certain of our direct and indirect domestic subsidiaries have a senior secured revolving credit facility with a syndicate of lenders (as amended from time to time, the "U.S. revolving credit facility"). On June 14, 2022 we amended our U.S. revolving credit facility, increasing our borrowing capacity to $250.0 million in the aggregate, including up to $150.0 million under a letter of credit sub-facility. On July 22, 2025, we further amended the U.S. revolving credit facility to, among other items, extend the maturity date of the facility to July 22, 2030 and revise the calculation of Term SOFR Adjustment to 0.10% per annum for all interest periods.

Any letters of credit issued and outstanding under the U.S. revolving credit facility reduce our borrowing availability on a dollar-for-dollar basis. At September 30, 2026, there wereno outstanding borrowings and $33.1 million of outstanding letters of credit issued under our U.S. revolving credit facility. Principal payments, if any, are due upon maturity of the U.S. revolving credit facility and may be prepaid without penalty.

Borrowing Base. The availability of funds under the U.S. revolving credit facility is limited by a specified borrowing base consisting of the Borrower's accounts receivable and inventory which meets the eligibility criteria.

Guaranty. The Borrowers' obligations under the U.S. revolving credit facility are guaranteed by certain of our domestic subsidiaries and secured by a continuing lien upon and a security interest in all of the Borrowers' accounts receivable, inventory and certain bank accounts. Each Borrower is liable for any and all obligations under the U.S. revolving credit facility on a joint and several basis.

Interest Rates and Fees. Any amounts outstanding under the U.S. revolving credit facility will bear interest at our option of either the secured overnight financing rate ("SOFR") or a base rate, plus, in each case, an applicable interest margin. The applicable interest margin is determined based on the average daily availability for the immediately preceding quarter. In addition, we pay an unused line fee on undrawn amounts, less the amount of our letters of credit exposure. For standby letters of credit, we are required to pay a fee on the face amount of such letters of credit that varies depending on whether the letter of

credit exposure is cash collateralized.

Prepayments. We can make prepayments of amounts outstanding under the U.S. revolving credit facility, in whole or in part, without premium or penalty, subject to standard breakage costs, if applicable. We may be required to apply the proceeds

from sales of collateral accounts, other than sales of inventory in the ordinary course of business, to repay amounts outstanding under the revolving credit facility and correspondingly reduce the commitments there under.

Covenants. The U.S. revolving credit facility contains customary covenants, including restrictions on mergers and acquisitions, indebtedness, affiliate transactions, liens, dividends and distributions, dispositions of collateral, investments, and prepayments of indebtedness, as well as a covenant that requires the Borrowers to maintain certain minimum liquidity or availability requirements.

Events of Default. The U.S. revolving credit facility also includes customary events of default, including nonpayment, misrepresentation, breach of covenant, bankruptcy, change of ownership, certain judgments and certain cross defaults. Upon the occurrence of an event of default, commitments under the U.S. revolving credit facility may be terminated and amounts outstanding may be accelerated and declared immediately due and payable.

Iceland Revolving Credit Facility

General. Our wholly-owned subsidiary, Nordural Grundartangi ehf ("Grundartangi"), entered into a revolving credit facility agreement with Landsbankinn hf., as amended (the "Iceland revolving credit facility"), which provides for borrowings of up to $100.0 million in the aggregate. Under the terms of the Iceland revolving credit facility, when Grundartangi borrows funds it will designate a repayment date, which may be any date prior to the maturity of the Iceland revolving credit facility. At September 30, 2026, there wereno outstanding borrowings under our Iceland revolving credit facility. On July 14, 2026, we amended the Iceland Revolving Credit Facility to extend the maturity date to December 9, 2028.

Borrowing Base. The availability of funds under the Iceland revolving credit facility is limited by a specified borrowing base consisting of inventory and accounts receivable of Grundartangi.

Security. Grundartangi's obligations under the Iceland revolving credit facility are secured by a general bond under which Grundartangi's inventory and accounts receivable are pledged to secure full payment of the loan.

Interest Rates and Fees. Any amounts outstanding under the Iceland revolving credit facility will bear interest at SOFR plus a margin per annum.

Prepayments. Any outstanding borrowings may be prepaid without penalty or premium in whole or in part.

Covenants. The Iceland revolving credit facility contains customary covenants, including restrictions on mergers and acquisitions, dispositions of assets, compliance with permits, laws and payment of taxes, as well as a covenant that requires Grundartangi to maintain a certain minimum equity ratio.

Events of Default. The Iceland revolving credit facility also includes customary events of default, including nonpayment, loss of license, cessation of operations, unlawfulness, breach of covenant, bankruptcy, change of ownership, certain judgments and certain cross defaults. Upon the occurrence of an event of default, commitments under the Iceland revolving credit facility may be terminated and amounts outstanding may be accelerated and declared immediately due and payable.

Vlissingen Credit Facility

On December 9, 2022, Vlissingen entered into a Facility Agreement with Glencore International AG, which was amended and extended on October 1, 2024 and on November 4, 2026 (as amended, the "Vlissingen Credit Facility"). The availability period for borrowings under the Vlissingen Credit Facility ends on December 2, 2028. Pursuant to the terms of the Vlissingen

Credit Facility, Vlissingen may borrow from time to time up to $90.0 million in one or more loans. As of September 30, 2026, there wereno outstanding borrowings under the Vlissingen Credit Facility.

Security. Vlissingen’s obligations under the Vlissingen Credit Facility are secured by liens on the ground lease on which Vlissingen’s facilities are located, Vlissingen’s moveable assets, financial assets, receivables and other assets, and Vlissingen’s shares.

Interest Rates and Fees. Through December 1, 2026, amounts outstanding under the Vlissingen Credit Facility will bear interest at a variable interest rate equal to the 1-month SOFR rate plus 3.687 percentage points, subject to an absolute maximum level of 9.00% and an absolute minimum level of 7.00%. On and after December 2, 2026, amounts outstanding under the Vlissingen Credit Facility will bear interest at a variable interest rate equal to the 1-month SOFR rate plus 3.687 percentage points, subject to an absolute maximum level of 10.00% and an absolute minimum level of 8.00%.

Prepayments. Any outstanding borrowings may be prepaid without penalty or premium in whole or in part without any charge, fee premium or penalty.

Covenants. The Vlissingen Credit Facility contains customary covenants including with respect to mergers, guarantees and preservation and dispositions of assets.

Events of Default. The Vlissingen Credit Facility also includes customary events of default, including nonpayment, breach of any provision or representation under the agreement, and certain cross-default and insolvency events. Upon the occurrence of an event of default, commitments under the Vlissingen Credit Facility may be terminated and amounts outstanding may be accelerated and declared immediately due and payable.

Covenant Compliance

As of September 30, 2026, we and our subsidiaries were in compliance with financial covenants or maintained availability above applicable covenant triggers.

Hancock County Industrial Revenue Bonds

As part of the purchase price for our acquisition of the Hawesville facility, we assumed IRBs which were issued in connection with the financing of certain solid waste disposal facilities constructed at the Hawesville facility. The IRBs bore interest at a variable rate not to exceed 12% per annum determined weekly based upon prevailing rates for similar bonds in the industrial revenue bond market and interest on the IRBs is paid quarterly. The IRBs were secured by a letter of credit in the amount issued under our U.S. revolving credit facility and were scheduled to mature in April 2028. In connection with our sale of the Hawesville facility, on February 2, 2026, we effected a final draw under the letter of credit, defeased the IRBs and related Indenture, and irrevocably directed the Trustee to redeem the IRBs on April 1, 2026. Immediately following the final draw under the letter of credit, we terminated the letter of credit. As a result of the defeasance, the IRBs were considered extinguished as of February 2, 2026. The Trustee redeemed the IRBs on April 1, 2026.

Surety Bond Facility

As part of our normal business operations, we are required to provide surety bonds or issue letters of credit in certain states in which we do business as collateral for certain workers' compensation obligations. In June 2022, we entered into a surety bond facility with an insurance company to provide such bonds when applicable. As of September 30, 2026, we had issued surety bonds totaling $6.6 million.