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☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)

For the quarterly period ended March 31, 2024

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)

For the transition period from _______ to _______.

Commission file number 001-34474

(Exact name of registrant as specified in its charter)

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. ☒ Yes ☐ No

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). ☒ Yes ☐ No

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer”, “smaller reporting company” and "emerging growth company" in Rule 12b-2 of the Exchange Act. (Check one):

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

☐ Yes ☒ No

The registrant had 92,700,495 shares of common stock outstanding at April 30, 2024.

CENTURY ALUMINUM COMPANY
CONSOLIDATED STATEMENTS OF OPERATIONS
(in millions, except per share amounts)
(Unaudited)
			Three months ended March 31,
			2024						2023
NET SALES:
Related parties			$	315.0					$	412.2
Other customers			174.5						140.2
Total net sales			489.5						552.4
Cost of goods sold			473.0						504.3
Gross profit			16.5						48.1
Selling, general and administrative expenses			14.1						13.4
Other operating expense - net			0.5						7.2
Operating income			1.9						27.5
Interest expense - affiliates			(1.8)						—
Interest expense			(7.4)						(8.7)
Interest income			0.7						0.3
Net gain (loss) on forward and derivative contracts			7.4						(57.6)
Bargain purchase gain			245.9						—
Other loss - net			(1.5)						(0.3)
Income (loss) before income taxes			245.2						(38.8)
Income tax (expense) benefit			(0.5)						0.2
Net income (loss)			244.7						(38.6)
Net loss attributable to noncontrolling interests			(2.1)						—
Net income (loss) attributable to Century stockholders			246.8						(38.6)
Less: net income allocated to participating securities			13.2						—
Net income (loss) allocated to common stockholders			$	233.6					$	(38.6)
INCOME (LOSS) ATTRIBUTABLE TO CENTURY STOCKHOLDERS PER COMMON SHARE:
Basic			$	2.52					$	(0.42)
Diluted			2.26						(0.42)
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING:
Basic			92.7						92.3
Diluted			98.7						92.3

(amounts in millions, except share and per share amounts)

(Unaudited)

1.General

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, 2023. 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 three months of 2024 are not necessarily indicative of the results that may be expected for the year ending December 31, 2024. 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.

Our consolidated financial statements include the consolidated results of the Jamalco joint venture, an unincorporated joint venture between the Company and Clarendon Alumina Production Limited. Clarendon Alumina Production's interest in the joint venture is reflected as noncontrolling interest on the accompanying Consolidated Balance Sheets.

In November 2023, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update (“ASU”) 2023-07, “Improvements to Reportable Segment Disclosures.” (“ASU 2023-07”). Among other changes, the ASU requires disclosure of significant segment expenses and extends certain annual disclosures to interim periods. The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2024. Early adoption is permitted. The Company is currently evaluating the requirements of ASU 2023-07.

2.Acquisition of Jamalco

On May 2, 2023, our wholly-owned subsidiary, Century Aluminum Jamaica Holdings, Inc., completed the acquisition of all the outstanding share capital of General Alumina Holdings Limited, the holder of a 55% interest in Jamalco JV ("Jamalco"), an unincorporated joint venture engaged in bauxite mining and alumina production in Jamaica. The remaining 45% interest in Jamalco is owned by Clarendon Alumina Production Limited ("CAP"), which is owned by the Government of Jamaica. The results of operations have been included in the consolidated financial statements since the acquisition date. The purchase price of the acquisition was $1.00, primarily due to the seller experiencing financial distress following curtailment of Jamalco's operations in the second half of 2021 due to a facility fire, with operations restarting in the second half of 2022.

The acquisition was accounted for as a business combination under the acquisition method of accounting in accordance with ASC 805 - Business Combinations, resulting in the Company recognizing the assets and liabilities at fair value with the excess over fair value of consideration transferred to the seller presented as a bargain purchase gain of $245.9 million recognized within the Consolidated Statements of Operations for the three months ended March 31, 2024. The Company finalized its purchase accounting as of March 31, 2024.

The following table represents the allocation of the estimated fair value of identified assets acquired, liabilities assumed and noncontrolling interest as of March 31, 2024

The following unaudited pro forma financial information reflects the results of operations of the Company for the three months ended March 31, 2023 as if the acquisition of Jamalco had been completed on January 1, 2023. This unaudited pro forma financial information has been prepared for informational purposes and is not necessarily indicative of the actual consolidated results of operations had the acquisition been completed on January 1, 2023, nor is the information indicative of future results of operations of the combined companies.

3.Curtailment of Operations - Hawesville

In August 2022, we fully curtailed production at the Hawesville facility and expect to continue to maintain the plant with the intention of restarting operations when market conditions permit, including energy prices returning to more normalized levels and aluminum prices maintaining levels that can support the on-going costs and capital expenditures necessary to restart and operate the plant.

For the three months ended March 31, 2024 and 2023, we incurred curtailment charges of approximately $0.6 million and $7.0 million, respectively, including $5.4 million related to demand capacity charges for power during three months ended March 31, 2023. In addition, these charges were partially offset by income related to scrap and materials sales of $0.5 million and $0.7 million for the three months ended March 31, 2024 and 2023, respectively, recognized in Other operating expense - net within the Consolidated Statements of Operations.

4.Related Party Transactions

The significant related party transactions occurring during the three months ended March 31, 2024 and 2023 are described below. We believe all of our transactions with related parties are at prices that approximate market.

As of March 31, 2024, Glencore plc and its affiliates (together "Glencore") beneficially owned 42.9% of Century’s outstanding common stock (46.0% on a fully-diluted basis assuming the conversion of all of the Series A Convertible Preferred Stock) and all of our outstanding Series A Convertible Preferred Stock. See Note 8. Shareholders' Equity for a description of our outstanding Series A Convertible Preferred Stock. Century and Glencore enter into various transactions from time to time such as the purchase and sale of primary aluminum, purchase and sale of alumina and other raw materials, tolling agreements as well as forward financial contracts and borrowing and other debt transactions.

For the three months ended March 31, 2024 and 2023, we derived approximately 64.3% and 75.0% of our consolidated net sales from Glencore, respectively.

Glencore purchases aluminum produced at our U.S. smelters at prices based on the 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 primarily 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 the three months ended March 31, 2024 and 2023, the Company recognized $35.5 million and $21.0 million, respectively, of revenue related to alumina sales to Glencore.

We purchase a portion of our alumina and certain other raw material requirements from Glencore. Alumina purchases from Glencore during the three months ended March 31, 2024 and March 31, 2023, were priced based on published alumina and aluminum indices as well as fixed prices.

We have certain financial contracts with Glencore. See Note 15. Derivatives regarding these forward financial sales contracts.

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

(1)Includes settlements of financial contract positions.

On December 9, 2022, Vlissingen entered into a Facility Agreement with Glencore International AG pursuant to which Vlissingen may borrow from time to time up to $90.0 million (the "Vlissingen Facility Agreement") in one or more loans at a fixed interest rate equal to 8.75% per annum and payable on December 2, 2024. See Note 11. Debt for additional information. Borrowings under the Vlissingen Facility Agreement are expected to be used for general corporate and working capital purposes of Century and its subsidiaries.

In September 2023, our wholly owned subsidiary Nordural Grundartangi ehf ("Grundartangi"), entered into a structured repurchase arrangement ("Agreement") with an affiliate of Glencore and sold 390,000 European Union Allowances ("Carbon Credits") at a price of €82.18 per Carbon Credit, for an aggregate amount of €32.1 million. The terms of the transaction

permitted Grundartangi to repurchase the same number of Carbon Credits by December 21, 2023, at a price of €83.72 per Carbon Credit, for an aggregate amount of €32.7 million. In December 2023, the Agreement was amended ("Amended Agreement") to extend the repurchase window to March 25, 2024, and increased the repurchase price to €85.13 per Carbon Credit, for an aggregate amount of €33.2 million. In addition, Grundartangi entered into a second repurchase agreement ("Second Agreement") with Glencore to sell 40,000 Carbon Credits at a price of €69.30 per Carbon Credit and to repurchase the same number of Carbon Credits at a price of €70.71 per Carbon Credit for an aggregate amount of €2.8 million.

In March 2024, the Amended Agreement was amended to extend the repurchase window from March 25, 2024 to August 30, 2024 and the repurchase price was revised to €87.01 per Carbon Credit, for an aggregate amount of €33.9 million. In addition, the Second Agreement was amended to extend the repurchase window from March 25, 2024 to August 30, 2024 and revised the repurchase price to €72.59 per Carbon Credit, for an aggregate amount of €2.9 million. Due to the repurchase element of these transactions, the Company retains substantially all of the remaining benefits of the assets and has accounted for the transaction as a financing arrangement in accordance with Topic 606, Revenue from Contracts with Customers ("ASC 606").

We disaggregate our revenue by geographical region as follows:

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 volume delivered, market price of primary aluminum, which is based on the LME, plus regional premiums and any value-added product premiums. We have also entered into agreements with our customers to sell certain amounts of alumina at market-based prices.

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 $52.0 million and $30.6 million, as of March 31, 2024 and December 31, 2023, respectively.

We measure certain of our assets and liabilities at fair value. Fair value represents the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date.

In general, reporting entities should apply valuation techniques to measure fair value that maximize the use of observable inputs and minimize the use of unobservable inputs. Observable inputs are developed using market data and reflect assumptions that market participants would use when pricing the asset or liability. Unobservable inputs are developed using the best information available about the assumptions that market participants would use when pricing the asset or liability.

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 the reporting entity 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 and 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.

The following table presents the fair value reconciliation of Level 3 assets and liabilities measured at fair value on a recurring basis. There was no activity related to Level 3 assets and liabilities measured at fair value on a recurring basis for the three months ended March 31, 2024.

(1)Gains and losses are presented in the Consolidated Statement of Operations within the line item "Net gain (loss) on forward and derivative contracts."

(2)Transfers into Level 3 due to period of time remaining in derivative contract.

Basic and diluted earnings per share ("EPS") amounts are calculated using the two-class method. Under the two-class method, net earnings are allocated to each class of common stock and participating securities as if all of the net earnings for the period had been distributed. Basic earnings per common share excludes dilution and is calculated by dividing net income (loss) allocated to common stockholders by the weighted average number of common shares outstanding during the period. Diluted EPS amounts assume the issuance of common stock for all potentially dilutive securities. Prior to the three months ended March 31, 2024, diluted EPS amounts were calculated by applying the if-converted method as net income allocated to participating securities was not significant.

The following table shows the basic and diluted (loss) 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.

As of March 31, 2024 and December 31, 2023, we had 195,000,000 shares of common stock, $0.01 par value per share, authorized under our Restated Certificate of Incorporation, of which 99,887,016 shares were issued and 92,700,495 shares were outstanding at March 31, 2024, and 99,876,385 were issued and 92,689,864 shares were outstanding at December 31, 2023.

The rights, preferences and privileges of holders of our common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of our preferred stock which are currently outstanding, including our Series A Convertible Preferred Stock, or which we may designate and issue in the future.

As of March 31, 2024 and December 31, 2023, we had 5,000,000 shares of preferred stock, $0.01 par value per share, authorized under our Restated Certificate of Incorporation. Our Board of Directors may issue preferred stock in one or more series and determine for each series the dividend rights, conversion rights, voting rights, redemption rights, liquidating preferences, sinking fund terms and the number of shares constituting that series, as well as the designation thereof. Depending upon the terms of preferred stock established by our Board of Directors, any or all of the preferred stock could have preference over the common stock with respect to dividends and other distributions and upon the liquidation of Century. In addition, issuance of any shares of preferred stock with voting powers may dilute the voting power of the outstanding common stock.

Shares Authorized and Outstanding. In 2008, we issued 160,000 shares of our Series A Convertible Preferred Stock. Glencore holds all of the issued and outstanding Series A Convertible Preferred Stock. At March 31, 2024 and December 31, 2023, 52,238 and 52,284 shares of Series A Convertible Preferred Stock were outstanding, respectively.

The issuance of common stock under our stock incentive programs, debt exchange transactions and any stock offering that excludes Glencore participation triggers anti-dilution provisions of the preferred stock agreement and results in the automatic conversion of Series A Convertible Preferred Stock shares into shares of common stock. The conversion of preferred to common shares is 100 shares of common stock for each share of preferred stock. Our Series A Convertible Preferred Stock has a par value of $0.01 per share.  

In 2011, our Board of Directors authorized a $60.0 million common stock repurchase program and during the first quarter of 2015, our Board of Directors increased the size of the program by $70.0 million. Under the program, Century is authorized to repurchase up to $130.0 million of our outstanding shares of common stock, from time to time, on the open market at prevailing market prices, in block trades or otherwise. The timing and amount of any shares repurchased will be determined by our management based on its evaluation of market conditions, the trading price of our common stock and other factors. The stock repurchase program may be suspended or discontinued at any time.

Shares of common stock repurchased are recorded at cost as treasury stock and result in a reduction of shareholders’ equity in the Consolidated Balance Sheets. From time to time, treasury shares may be reissued as contributions to our employee benefit plans and for the conversion of convertible preferred stock. When shares are reissued, we use an average cost method for determining cost. The difference between the cost of the shares and the reissuance price is added to or deducted from additional paid-in capital.

Through March 31, 2024 we repurchased 7,186,521 shares of common stock for an aggregate purchase price of $86.3 million. We have made no repurchases since April 2015 and have approximately $43.7 million remaining under the repurchase program authorization as of March 31, 2024.

For the three months ended March 31, 2024 and 2023, we recorded an income tax expense of $0.5 million and a tax benefit of $0.2 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, adjusted for discrete items. 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 pre-tax accounting income/loss as reported on the Consolidated Statement of Operations.

As of March 31, 2024, all of Century's U.S. and certain foreign deferred tax assets, net of deferred tax liabilities, continue to be subject to a valuation allowance.

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 December 14, 2023, the U.S. Department of the Treasury and the Internal Revenue Service released proposed rules to provide guidance on the production tax credit requirements under Internal Revenue Code Section 45X (the “Proposed Regulations”). The Proposed Regulations provide guidance on rules that taxpayers must satisfy to qualify for the IRA Section 45X tax credit. For the three months ended March 31, 2024, the Company recognized a reduction of $11.9 million in Cost of goods sold and a reduction of $0.7 million in Selling, general and administrative expenses within the Consolidated Statements of Operations, resulting in an equally offsetting receivable. As of March 31, 2024 and December 31, 2023, the Company recognized a Manufacturing credit receivable of $57.9 million and $59.3 million, respectively, and as of March 31, 2024, recognized a non-current receivable of $14.0 million within Other assets on the Consolidated Balance Sheets.

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.

(1)The IRBs are classified as current liabilities because they are remarketed weekly and could be required to be repaid upon demand if there is a failed remarketing. The interest rate at March 31, 2024 was 3.77%.

(2)We incur interest at a base rate plus applicable margin as defined within the agreement. The interest rate at March 31, 2024 was 9.25%.

(3)We incur interest at base rate plus applicable margin as defined within the agreement. The interest rate at March 31, 2024 was 8.83%.

(4)We incur interest at a base rate plus applicable margin as defined within the agreement. The interest rate at March 31, 2024 was 8.84%.

(5)We incur interest at a fixed rate equal to 8.75%.

In April 2021, we issued $250.0 million in aggregate principal amount of 7.5% senior secured notes due April 1, 2028 (the "2028 Notes"). We received proceeds of $245.2 million, after payment of certain financing fees and related expenses. The 2028 Notes bear interest semi-annually in arrears on April 1 and October 1 of each year, which began on October 1, 2021, at a rate of 7.5% per annum in cash. The 2028 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.

As of March 31, 2024, the total estimated fair value of the 2028 Notes was $251.2 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.

In April 2021, we completed a private offering of $86.3 million aggregate principal amount of convertible senior notes due May 1, 2028 unless earlier converted, repurchased, or redeemed (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 Convertible Notes bear interest semi-annually in arrears on May 1 and November 1 of each year, which began on November 1, 2021, at a rate of 2.75% per annum in cash.

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 March 31, 2024, the conversion rate remains unchanged.

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.

As of March 31, 2024, the if-converted value of the Convertible Notes does not exceed the outstanding principal amount.

As of March 31, 2024, the total estimated fair value of the Convertible Notes was $88.0 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.

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. The U.S. revolving credit facility matures on June 14, 2027.

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 March 31, 2024, there were $17.0 million in outstanding borrowings and $58.0 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.

Our wholly-owned subsidiary, Nordural Grundartangi ehf ("Grundartangi"), entered into a revolving credit facility agreement with Landsbankinn hf., dated November 2013, as amended (the "Iceland revolving credit facility"), which originally provided for borrowings of up to $50.0 million in the aggregate. On February 4, 2022, we amended the Iceland revolving credit facility and increased the facility amount to $80.0 million. On September 28, 2022, we further amended the Iceland revolving credit facility and increased the facility amount 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 March 31, 2024, there were $32.0 million in outstanding borrowings under our Iceland revolving credit facility. The Iceland revolving credit facility has a term through December 2026.

On November 2, 2021, in connection with the casthouse project at Grundartangi, we entered into an eight-year Term Facility Agreement with Arion Bank hf, to provide for borrowings up to $130.0 million (the "Casthouse Facility"). Under the Casthouse Facility, repayments of principal amounts will be made in equal quarterly installments equal to 1.739% of the principal amount, the first payment occurring in July 2024, with the remaining 60% of the principal amount to be paid no later than the termination date in December 2029. As of March 31, 2024, there were $130.0 million in outstanding borrowings under the Casthouse Facility.

Our wholly-owned subsidiary, Grundartangi, entered into a Term Facility Agreement with Arion Bank hf, dated September 2022, (the "Iceland Term Facility") to provide for borrowings up to €13.6 million. Repayments of principal amounts were made in equal monthly installments, the first payment occurring in February 2023, with the remainder of the principal amount paid in January 2024. Borrowings under the Iceland Term Facility bore interest at a rate equal to 3.2% plus EUR EURIBOR 1 month as published at any time by the European Money Markets Institute. The Iceland Term Facility has been repaid in full and has terminated pursuant to its terms in the first quarter of 2024.

On December 9, 2022, Vlissingen entered into a Facility Agreement with Glencore International AG pursuant to which Vlissingen may borrow from time to time up to $90.0 million (the "Vlissingen Facility Agreement") in one or more loans at a fixed interest rate equal to 8.75% per annum and payable on December 2, 2024, the maturity date of the Vlissingen Facility Agreement. As of March 31, 2024, there were $10.0 million in outstanding borrowings under the Vlissingen Facility Agreement.

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 bear 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 are secured by a letter of credit issued under our U.S revolving credit facility and mature in April 2028.

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 March 31, 2024, we had issued surety bonds totaling $6.6 million. As we had previously guaranteed our workers' compensation obligations through issuance of letters of credit against our revolving credit facility, the surety bond issuance increases credit facility availability.

We have pending against us or may be subject to various lawsuits, claims and proceedings related primarily to employment, commercial, stockholder, environmental, safety and health matters and are involved in other matters that may give rise to contingent liabilities. While the results of such matters and claims cannot be predicted with certainty, we believe that the ultimate outcome of any such matters and claims will not have a material adverse impact on our financial condition, results of operations or liquidity. However, because of the nature and inherent uncertainties of litigation and estimating liabilities, should the resolution or outcome of these actions be unfavorable, our business, financial condition, results of operations and liquidity could be materially and adversely affected.

In evaluating whether to accrue for losses associated with legal or environmental contingencies, it is our policy to take into consideration factors such as the facts and circumstances asserted, our historical experience with contingencies of a similar nature, the likelihood of our prevailing and the severity of any potential loss. For some matters, no accrual is established because we have assessed our risk of loss to be remote. Where the risk of loss is probable and the amount of the loss can be reasonably estimated, we record an accrual, either on an individual basis or with respect to a group of matters involving similar claims, based on the factors set forth above. While we regularly review the status of, and our estimates of potential liability associated with, contingencies to determine the adequacy of any associated accruals and related disclosures, the ultimate amount of loss may differ from our estimates.

In November 2009, Century Aluminum of West Virginia ("CAWV") filed a class action complaint for declaratory judgment against the United Steel, Paper and Forestry, Rubber, Manufacturing, Energy, Allied Industrial and Service Workers International Union ("USW"), the USW’s local and certain CAWV retirees, individually and as class representatives ("CAWV Retirees"), seeking a declaration of CAWV’s rights to modify/terminate retiree medical benefits. Later in November 2009, the USW and representatives of a retiree class filed a separate suit against CAWV, Century Aluminum Company, Century Aluminum Master Welfare Benefit Plan, and various John Does with respect to the foregoing. On August 18, 2017, the District Court for the Southern District of West Virginia approved a settlement agreement in respect of these actions, pursuant to which agreement, CAWV agreed to make payments into a trust for the benefit of the CAWV Retirees in the aggregate amount of $23.0 million over the course of ten years. Upon approval of the settlement, we paid $5.0 million to the aforementioned trust in September 2017 and recognized a gain of $5.5 million to arrive at the then-net present value of $12.5 million. CAWV has agreed to pay the remaining amounts under the settlement agreement in annual increments of $2.0 million for nine years. As of March 31, 2024, $2.0 million was recorded in Other current liabilities and $3.4 million was recorded in Other liabilities on the Consolidated Balance Sheets.

In 2013, we entered into a settlement agreement with the Pension Benefit Guaranty Corporation (the "PBGC") regarding an alleged "cessation of operations" at our Ravenswood facility (the "PBGC Settlement Agreement"). Pursuant to the terms of the PBGC Settlement Agreement, we agreed to make additional contributions (above any minimum required contributions) to our defined benefit pension plans totaling approximately $17.4 million. Under certain circumstances, in periods of lower primary aluminum prices relative to our cost of operations, we were able to defer one or more of these payments, provided that we provide the PBGC with acceptable security for such deferred payments. We historically elected to defer certain payments under the PBGC Settlement Agreement and provided the PBGC with the appropriate security. In October 2021, we amended the PBGC Settlement Agreement (the "Amended PBGC Settlement Agreement") such that we removed the deferral mechanism and agreed to contribute approximately $2.4 million per year to our defined benefit pension plans for a total of approximately $9.6 million, over the next four years beginning on November 30, 2022 and ending on November 30, 2025, subject to acceleration if certain terms and conditions are met in such amendment. As of March 31, 2024, we made contributions of $6.9 million and no payments for the three months ended March 31, 2024 related to the Amended PBGC Settlement Agreement.

Hawesville has a power supply arrangement with Kenergy and Century Marketer, LLC (“Century Marketer"), Century's wholly-owned subsidiary that acts as a MISO market participant. Under this arrangement, Hawesville gets access to power at Midcontinent Independent System Operator ("MISO") pricing plus transmission and other costs. As the MISO Market Participant, Century Marketer purchases power from MISO for resale to Kenergy, which then resells the power to Hawesville.

Century Marketer's power supply arrangement with Kenergy has an effective term through May 31, 2028, with automatic one-year extensions unless either party provides one-year notice of termination prior to the May 31 anniversary date. Similarly, Kenergy's power supply contract with Hawesville has a term through December 31, 2025, with automatic one-year extensions unless either party provides one-year notice of termination prior to the December 31 anniversary date.

Sebree has a power supply arrangement with Kenergy and Century Marketer, LLC (“Century Marketer"), Century's wholly-owned subsidiary that acts as a MISO market participant. Under this arrangement, Sebree gets access to power at Midcontinent Independent System Operator ("MISO") pricing plus transmission and other costs. As the MISO Market Participant, Century Marketer purchases power from MISO for resale to Kenergy, which then resells the power to Sebree. Century Marketer's power supply arrangement with Kenergy has an effective term through May 31, 2028, with automatic one-year extensions unless either party provides one-year notice of termination prior to the May 31 anniversary date. Similarly, Kenergy's power supply contract with Sebree has a term through December 31, 2025, with automatic one-year extensions unless either party provides one-year notice of termination prior to the December 31 anniversary date.

CASC has a power supply agreement with Santee Cooper that has an effective term through December 2026. Under this power supply agreement, 100% of Mt. Holly’s electrical power requirements are supplied from Santee Cooper’s generation at cost of service based rates.

Grundartangi has power purchase agreements for approximately 545 MW of aggregate power with HS Orka hf ("HS"), Landsvirkjun and Orkuveita Reykjavikur ("OR"). These power purchase agreements expire on various dates from 2026 through 2036 (subject to extension). The power purchase agreements with each of HS and OR provide power at LME-based variable rates for the duration of these agreements. Under the terms of the Landsvirkjun agreement, Landsvirkjun will provide up to 182 MW over time to support the most recent capacity creep requirements and the new billet casthouse at Grundartangi. The Landsvirkjun agreement provides for fixed rates on most of the 182 MW, with a variable rate applicable to a smaller portion of the power through December 31, 2026. Grundartangi also has a separate 25 MW power purchase agreement with Landsvirkjun at LME-based variable rate.

The bargaining unit employees at our Grundartangi, Vlissingen, Hawesville, Sebree and Jamalco facilities are represented by labor unions, representing approximately 59% of our total workforce.

Approximately 86% of Grundartangi’s work force is represented by five labor unions, governed by a labor agreement that establishes wages and work rules for covered employees. This agreement is effective through December 31, 2024.

100% of Vlissingen's work force is represented by the Federation for the Metal and Electrical Industry ("FME"), a Netherlands' employers' organization for companies in the metal, electronics, electrical engineering and plastic sectors. The FME negotiates working conditions with trade unions on behalf of its members, which, when agreed upon, are then applicable to all employees of Vlissingen. The current labor agreement is effective through May 31, 2024, and Vlissingen is currently in the process of negotiating a new contract with the FME.

Approximately 40% of our U.S. based work force is represented by USW through separately negotiated labor agreements for each facility. The labor agreement for Hawesville employees is effective through April 1, 2026. Upon announcement of the temporary curtailment, Hawesville and the USW local union entered into effects bargaining. An agreement was reached on July 19, 2022, covering the curtailment period. Century Sebree's labor agreement with the USW for its employees is effective through October 28, 2028. Mt. Holly employees are not represented by a labor union.

Approximately 62% of Jamalco’s work force is represented by the Union of Technical, Administrative, and Supervisory Personnel ("UTASP") through separately negotiated labor agreements for hourly and salaried employee groups. Both contracts were effective through December 31, 2023. Jamalco is currently in the process of negotiating new contracts with both the salaried and hourly employee groups.

We have a contingent obligation in connection with the "unwind" of a contractual arrangement between CAKY, Big Rivers Electric Corporation ("Big Rivers") and a third party and the execution of a long-term cost-based power contract with Kenergy, a member of a cooperative of Big Rivers, in July 2009. This contingent obligation consists of the aggregate payments made to Big Rivers by the third party on CAKY’s behalf in excess of the agreed upon base amount under the long-term cost-based power contract with Kenergy. As of March 31, 2024, the principal and accrued interest for the contingent obligation was $31.2 million, which was fully offset by a derivative asset. We may be required to make installment payments for the contingent obligation in the future. These payments are contingent based on the LME price of primary aluminum and the level of Hawesville’s operations. As of March 31, 2024, the LME forward market prices do not exceed the threshold for payment. In addition, based on the current level of Hawesville's operations, including the temporary curtailment, we believe that we will not be required to make payments on the contingent obligation during the term of the agreement, which expires in 2028. There can be no assurance that circumstances will not change thus accelerating the timing of such payments.

(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:

As of March 31, 2024, we had an open position of 26,181 tonnes related to LME forward financial sales contracts to fix the forward LME aluminum price. These contracts are expected to settle monthly through December 2024. 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 March 31, 2024, we had no open fixed for floating swaps.

We have entered into forward contracts to hedge the risk of fluctuations associated with the Icelandic Krona (ISK) and Euro for contracts related to the construction of the Grundartangi casthouse and the Sebree casthouse project denominated in these currencies ("casthouse currency hedges"). As of March 31, 2024, we had no open casthouse currency hedges.

We have entered into financial contracts to hedge a portion of our exposure at our operations to Heavy Fuel Oil (“HFO price swaps”). The HFO volume is measured per barrel. As of March 31, 2024, we had an open position of 245,000 barrels. The HFO price swaps are expected to settle monthly through February 2025.

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 March 31, 2024 and December 31, 2023, the Company had not 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 March 31, 2024 and December 31, 2023, respectively:

(1)Commodity contracts reflect our outstanding LME forward financial sales contracts and HFO price swaps. At March 31, 2024, $3.4 million of Due to affiliates was related to commodity contracts with Glencore. At December 31, 2023, $6.4 million of Due to affiliates was related to commodity contract liabilities with Glencore.

(2)Foreign exchange contracts reflect our outstanding FX swaps and the casthouse currency hedges.

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

(1)For the three months ended March 31, 2024, $4.0 million of the net gain was with Glencore, and for the three months ended March 31, 2023, $14.9 million of the net loss was with Glencore.

This quarterly report includes "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, which are subject to the "safe harbor" created by section 27A of the Securities Act of 1933, as amended, and section 21E of the Securities Exchange Act of 1934 (the "Exchange Act"), as amended. Forward-looking statements are statements about future events and are based on our current expectations. These forward-looking statements may be identified by the words “believe,” “expect,” “hope,” “target,” “anticipate,” “intend,” “plan,” “seek,” “estimate,” “potential,” “project,” “scheduled,” “forecast” or words of similar meaning, or future or conditional verbs such as “will,” “would,” “should,” “could,” “might,” or “may.”

Forward-looking statements in this quarterly report and in our other reports filed with the Securities and Exchange Commission (the "SEC"), for example, may include, but are not limited to, statements regarding:

•Our assessment of global and local financial and economic conditions;

•Our assessment of the aluminum market and aluminum prices (including premiums);

•Our assessment of alumina pricing, energy prices, both in the United States and Europe, costs associated with our other key raw materials and supply and availability of those key raw materials, including power (and related natural gas and coal), and the likelihood and extent of any power curtailments;

•Our assessment of power prices and availability for our U.S. and European operations;

•The impact of the wars in Ukraine and in the Middle East, including any sanctions and export controls targeting Russia and businesses tied to Russia and to sanctioned entities and individuals, including any possible impact on our business, operations, financial condition, results of operations, and global supply chains;

•The future financial and operating performance of the Company and its subsidiaries;

•Our ability to successfully manage market risk and to control or reduce costs;

•Our plans and expectations with respect to future operations of the Company and its subsidiaries, including any plans and expectations to curtail or restart production, including the expected impact of any such actions on our future financial and operating performance;

•Our plans and expectations with regards to future operations of our Mt. Holly smelter, including our expectations as to the restart of curtailed production at Mt. Holly including the timing, costs and benefits associated with restarting curtailed production;

•Our plans with regards to future operations of our Hawesville smelter, including our expectations as to the timing, costs and benefits associated with restarting curtailed production;

•Our plans and expectations with regards to the Grundartangi casthouse project, including our expectations as to the timing, costs and benefits associated with the Grundartangi casthouse project;

•Our plans and expectations with respect to the acquisition of a 55% interest in Jamalco, including our expectations as to the costs and benefits associated with this transaction;

•Our ability to successfully obtain and/or retain competitive power arrangements for our operations;

•The impact of Section 232 relief, including tariffs or other trade remedies, the extent to which any such remedies may be changed, including through exclusions or exemptions, and the duration of any trade remedy;

•The impact of any new or changed law, regulation, including, without limitation, sanctions or other similar remedies or restrictions or any changes in interpretation of existing laws or regulations;

•Our anticipated tax liabilities, benefits or refunds including the realization of U.S. and certain foreign deferred tax assets and liabilities;

•Our ability to qualify for and realize potential tax benefits under the Inflation Reduction Act of 2022 and the anticipated amounts of such benefits;

•Our ability to realize the full amount of the DOE $500 million grant, to negotiate favorable terms and conditions related to such grant, to raise additional capital through additional grants, incentives, subsidized loans and other debt and equity funding to support construction of a new aluminum smelter;

•Our ability to access existing or future financing arrangements and the terms of any such future financing arrangements;

•Our ability to repay or refinance debt in the future;

•Our ability to recover losses from our insurance;

•Our assessment and estimates of our pension and other postretirement liabilities, legal and environmental liabilities and other contingent liabilities;

•Our assessment of any future tax audits or insurance claims and their respective outcomes;

•Negotiations with current labor unions or future representation by a union of our employees;

•Our assessment of any information technology-related risks, including the risk from cyberattacks or other data security breaches, including the cybersecurity incident that occurred on February 16, 2022;

•Our plans and expectations regarding potential M&A and joint venture activity including our ability to consummate such transactions and our assessments of certain risks associated with the same, including, for example, unforeseen costs and expenses associated with unidentified liabilities, and difficulties integrating an acquired asset into our existing operations; and

•Our future business objectives, plans, strategies and initiatives, including our competitive position and prospects.

Where we express an expectation or belief as to future events or results, such expectation or belief is expressed in good faith and believed to have a reasonable basis. However, our forward-looking statements are based on current expectations and assumptions that are subject to risks and uncertainties which may cause actual results to differ materially from future results expressed, projected or implied by those forward-looking statements. Important factors that could cause actual results and events to differ from those described in such forward-looking statements can be found in the risk factors and forward-looking statements cautionary language contained in Item 1A. Risk Factors in our Annual Report on Form 10-K, quarterly reports on Form 10-Q and in other filings made with the SEC. Although we have attempted to identify those material factors that could cause actual results or events to differ from those described in such forward-looking statements, there may be other factors that could cause actual results or events to differ from those anticipated, estimated or intended. Many of these factors are beyond our ability to control or predict. Given these uncertainties, the reader is cautioned not to place undue reliance on our forward-looking statements. We undertake no obligation to update or revise publicly any forward-looking statements, whether as a result of new information, future events, or otherwise.

This Management’s Discussion and Analysis (“MD&A”) provides information that management believes is relevant to an assessment and understanding of the consolidated financial condition and results of operations of Century Aluminum Company and should be read in conjunction with the accompanying consolidated financial statements and related notes thereto. This MD&A contains “forward-looking statements” - see “Forward-Looking Statements” above.

We are a global producer of primary aluminum with aluminum reduction facilities, or "smelters," in the United States and Iceland. In addition to our primary aluminum assets, we have a 55% joint venture interest in the Jamalco bauxite mining operation and alumina refinery in Jamaica. The Jamalco refinery supplies a substantial amount of the alumina used for the production of primary aluminum at our Grundartangi, Iceland facility. We also own a carbon anode production facility located in the Netherlands. The key determinants of our results of operations and cash flows from operations are as follows:

•the price of primary aluminum, which is based on the London Metal Exchange ("LME") and other exchanges, plus any regional premiums and value-added product premiums;

•the cost of goods sold, the principal components of which are electrical power, alumina, carbon products, caustic soda, natural gas, heavy fuel oil and labor, which in aggregate represent more than 81% of our cost of goods sold; and

•our production volume and product mix.

On March 25, 2024, the U.S. Department of Energy ("DOE") Office of Clean Energy Demonstrations selected the Company to begin award negotiations for up to $500.0 million in Bipartisan Infrastructure Law and Inflation Reduction Act funding to build a new aluminum smelter as part of the Industrial Demonstrations Program ("IDP"). With the help of this funding, we plan to build the first new U.S. primary aluminum smelter in 45 years at a site within the Ohio/Mississippi River Basins.

On December 14, 2023, the U.S. Treasury Department’s issued proposed regulations implementing Section 45X of the Inflation Reduction Act, which provided guidance on rules taxpayers must satisfy to qualify for the tax credit. The government has incentivized the production of aluminum by offering a tax credit equal to 10% of eligible domestic production costs. Based on the proposed regulations, for the three months ended March 31, 2024, we recognized $11.9 million as a reduction in Cost of goods sold and $0.7 million as a reduction in Selling, general and administrative expenses within the Consolidated Statements of Operations, resulting in an equally offsetting receivable. As of March 31, 2024 and December 31, 2023, we recognized a Manufacturing credit receivable of $57.9 million and $59.3 million, respectively, and as of March 31, 2024, we recognized a non-current receivable of $14.0 million within Other assets on the Consolidated Balance Sheets.

In August 2022 we fully curtailed production at the Hawesville facility and expect to continue to maintain the plant with the intention of restarting operations when market conditions permit, including energy prices returning to more normalized levels and aluminum prices maintaining levels that can support the on-going costs and capital expenditures necessary to restart and operate the plant.

For the three months ended March 31, 2024 and 2023, we incurred curtailment charges of approximately $0.6 million and $7.0 million, respectively. These charges were partially offset by income related to scrap and materials sales of $0.5 million and $0.7 million for the March 31, 2024 and 2023 recognized in Other operating expense - net within the Consolidated Statements of Operations.

On May 2, 2023, our wholly-owned subsidiary, Century Aluminum Jamaica Holdings, Inc., acquired for $1.00 a 55% interest in Jamalco, an unincorporated joint venture with Clarendon Alumina Production Limited ("CAP"), which is owned by the Government of Jamaica. Jamalco is engaged in bauxite mining and alumina refining in Jamaica. The Company's wholly-owned subsidiary, General Alumina Jamaica Limited, is the manager of the Jamalco joint venture. Jamalco has alumina production capacity of approximately 1.4 million tonnes.

We finalized the purchase accounting and recognized a bargain purchase gain of $245.9 million within the Consolidated Statements of Operations for the three months ended March 31, 2024. Our historical financial statements for periods prior to May 2, 2023 do not include the results of Jamalco. Refer to Note 2. Acquisition of Jamalco for further information.

Starting in June 2023, we experienced power disruptions due to damage to the Jamalco power generation unit. The equipment returned to full capacity as of the end of October 2023, but we continued to experience some inefficiencies into the three months ended March 31, 2024. These inefficiencies led to higher production costs of alumina capitalized into inventory, some of which was shipped in the period. The cumulative impact of the equipment failure from the second quarter of 2023 through March 31, 2024 was approximately $38.8 million. We are actively engaged with our insurance carriers in connection with this equipment failure to determine the specific amount of coverage available to us, including any applicable deductibles.

The overall price of primary aluminum consists of three components: (i) the base commodity price, which is based on quoted prices on the LME and other exchanges; plus (ii) any regional premium (e.g., the Midwest premium for metal sold in the United States ("MWP") and the European Duty Paid premium for metal sold into Europe ("EDPP")); plus (iii) any value-added product premium. Each of these price components has its own drivers and variability.

The price of aluminum is influenced by a number of factors, including global supply-demand balance, inventory levels, speculative activities by market participants, production activities by producers, geopolitical and economic conditions, as well as production costs in major production regions. These factors can be highly variable and difficult to predict, which can lead to significant volatility in the price of aluminum. Increases or decreases in primary aluminum prices drive variability in our revenues (assuming all other factors are unchanged). From time to time, we may seek to manage our exposure to fluctuations in the LME price of primary aluminum and/or associated regional premiums through financial instruments designed to limit our downside price risk. Information regarding financial contracts is included in Note 15. Derivatives and risks associated with such financial contracts are disclosed specifically in our Annual Report on Form 10-K for the fiscal year ended December 31, 2023.

We saw continued declines in the pricing of aluminum through the first quarter of 2024, which was a continuation of Western demand challenges despite global LME inventory levels near all-time lows in 2023. The following table summarizes the average price for primary aluminum per tonne for the three months ended March 31, 2024 and 2023.

The following discussion for the three months ended March 31, 2024 reflects no change in production capacities, other than the continued curtailment of the Hawesville smelter, at our operating facilities.

Our net sales are impacted primarily by the LME price for aluminum, regional and value-added premiums, and the volume and product mix of aluminum we ship during the period. In general, our results reflect the LME and regional premium pricing on an approximately one to three month lag basis reflecting contractual terms with our customers.

Electrical power, alumina, carbon products, caustic soda, natural gas, heavy fuel oil and labor are the principal components of our cost of goods sold. Power costs can be volatile as a result of a number of factors beyond our control. See “Item 1A. Risk Factors — Increases in energy costs may adversely affect our business, financial position, results of operations and liquidity” in our Annual Report on Form 10-K for the year ended December 31, 2023. Power costs at our Kentucky plants are impacted by capacity demand charges, which are determined based on available power generating capacity in MISO, from which we purchase energy. The price of such capacity is set by auction annually in April, with the April 2023 auction resulting in capacity prices returning towards normalized levels which has reduced our capacity costs significantly from the prior year. Our expected capacity demand costs for power were approximately $1.5 million for the twelve months ending May 31, 2024, in addition to the market price of power used. We anticipate the capacity demand power costs resulting from the April 2024 auction for the twelve months ending May 31, 2025 to be approximately $3.1 million.

In 2024, energy prices in the U.S. and Europe have moderated from their previously elevated levels. European energy markets impact our Vlissingen facility in the Netherlands, which utilizes natural gas to produce anodes used in our Grundartangi operations. The energy market in Europe has historically been dependent upon imported natural gas from Russia, and the significant reduction in Russian gas supply to Europe has resulted in increased uncertainty with respect to the price and availability of natural gas. Adverse changes to European natural gas prices or availability could adversely affect operations at Vlissingen, and in turn operations at Grundartangi, if we are not able to source an alternative supply of anodes.

In general, our results reflect the market cost of alumina on an approximately three-month lag reflecting the terms of our alumina contracts and inventory levels.

(1)Excludes scrap aluminum sales, purchased aluminum and alumina sales.

Net sales decreased by $22.8 million for the three months ended March 31, 2024, compared to the three months ended December 31, 2023, primarily driven by unfavorable volume and sales mix of $16.0 million and unfavorable LME and regional premium price realizations of $4.5 million.

Net sales decreased by $62.9 million for the three months ended March 31, 2024, compared to the three months ended March 31, 2023, primarily driven by unfavorable volume and sales mix of $53.4 million and unfavorable LME and regional premium price realizations of $49.4 million. The change in net sales of aluminum was offset by $40.1 million attributable to alumina sales by Jamalco, whose operations were not reflected in our results of operations for the three months ended March 31, 2023.

Gross profit decreased by $22.9 million for the three months ended March 31, 2024, compared to the three months ended December 31, 2023, primarily attributable to the full-year 2023 IRA Section 45X credit recorded in the prior quarter and only one quarter of credit recorded in the current period, resulting in a decrease of $44.6 million, and unfavorable LME and regional price realizations of $4.5 million. These factors were partially offset by favorable raw material price realization of $22.1 million and favorable power price realization of $3.8 million.

Gross profit decreased by $31.6 million for the three months ended March 31, 2024, compared to the three months ended March 31, 2023, primarily driven by unfavorable LME and regional price realization of $49.4 million and unfavorable volume and sales mix of $36.9 million. These factors were partially offset by favorable raw material price realization of $32.3 million and power price realization of $22.4 million, and $11.9 million attributable to the IRA Section 45X credit.

Selling, general and administrative expenses increased by $6.0 million for the three months ended March 31, 2024, compared to the three months ended December 31, 2023, primarily driven by share-based compensation costs as a result of quarter over quarter changes in the Company's stock price and partially offset by recognition of the full-year 2023 IRA Section 45X tax credit recorded in the prior quarter and only one quarter of credit recorded in the current period.

Selling, general and administrative expenses increased by $0.7 million for the three months ended March 31, 2024, compared to the three months ended March 31, 2023, primarily driven by an increase in share-based compensation costs resulting from the increase of the Company's stock price between periods. and partially offset by $0.7 million reduction for Section 45X tax credit.

Net gain on forward and derivative contracts was $7.4 million for the three months ended March 31, 2024, a decrease of $4.5 million as compared to the three months ended December 31, 2023. The change was primarily driven by decreased losses on LME and heavy fuel oil forward contracts, attributable to favorable fluctuations in the forward prices and volume of contracts settled.

Net gain on forward and derivative contracts was $7.4 million for the three months ended March 31, 2024, a change of $65.0 million as compared to the three months ended March 31, 2023. The transition from loss to gain was primarily driven by reduced losses on Nord Pool derivative contracts which were settled in December 2023.

We finalized the purchase accounting related to the acquisition of 55% interest in Jamalco, which was acquired on May 2, 2023, and recognized a bargain purchase gain of $245.9 million for the three months ended March 31, 2024.

Income tax expense decreased by $6.1 million for the three months ended March 31, 2024, compared to the three months ended December 31, 2023, primarily driven by changes in the jurisdictional mix of earnings.

Income tax changed to expense of $0.5 million for the three months ended March 31, 2024, compared to a benefit of $0.2 million for the three months ended March 31, 2023, primarily driven by changes in the jurisdictional mix of earnings on a year-over-year basis. See Note 9. Income Taxes to the consolidated financial statements included herein for additional information.

Our principal sources of liquidity are available cash and cash flows from operations. We also have access to our existing U.S. and Iceland revolving credit facilities (collectively, the "revolving credit facilities") and have raised capital in the past through public equity and debt markets. Our principal uses of cash include the funding of operating costs (including post-retirement benefits), debt service requirements, capital expenditures, investments in our growth activities and in related businesses, working capital and other general corporate requirements.

We believe that cash provided from operations and financing activities will be adequate to cover our operations and business needs over the next twelve months. As of March 31, 2024, we had cash and cash equivalents of approximately $93.5 million and unused availability under our revolving credit facilities of $208.5 million (including $80.0 million under the Vlissingen Facility Agreement referred to below). Our cash and cash equivalents and unused availability under our revolving credit facilities comprise our liquidity position, which was $302.0 million as of March 31, 2024.

Our available cash and cash equivalents balance at March 31, 2024 was $93.5 million compared to $88.8 million at December 31, 2023.

Our statements of cash flows are summarized below: