Company: CENX
Filing Date: 2025-03-03
Form Type: 10-K
Source: 0000949157-25-000024
Chunk: 142

Company: CENTURY ALUMINUM CO
Filing Date: 2025-03-03
Form: 10-K
Item: Item 8
Chunk 142
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 for certain foreign and domestic retired employees. We accrue the estimated cost of providing postretirement benefits during the working careers of those employees who could become eligible for such benefits when they retire. We fund these benefits as the retirees submit claims.Retiree medical welfare changes Under the current Hawesville labor agreement, employees who retire during the term of the labor agreement have been divided into sub-groups based on attributes such as Medicare eligibility, hire date, age and years of service. Levels of benefits are defined for the sub-groups and range from no substantive change from the benefits provided under the previous labor agreement to replacement of the defined retiree medical benefit program with individual health reimbursement accounts for each eligible participant. The health reimbursement accounts are funded based on established rates per hour worked by each eligible participant. Eligible participants will be able to withdraw from their health reimbursement accounts to fund their own retiree medical coverage.During 2017, the Company amended its non-union retiree medical and life insurance benefits to align the Company’s benefits with the market and achieve a uniform retiree medical benefit design across the Company’s U.S. locations. Effective January 1, 2018, non-union retiree medical and life insurance benefits are restricted to current participants who meet the eligibility criteria as of January 1, 2018. Additionally, effective January 1, 2019, Century no longer administers non-union retiree medical, prescription drug, dental, or vision benefits and instead makes fixed health reimbursement account contributions. 

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CENTURY ALUMINUM COMPANYNOTES TO THE CONSOLIDATED FINANCIAL STATEMENTS(amounts in millions, except share and per share amounts)

Obligation and Funded StatusThe change in benefit obligation and change in plan assets as of December 31 are as follows:PensionOPEB2024202320242023Change in benefit obligation:    Benefit obligation at beginning of year$305.1 $263.0 $76.8 $73.7 Service cost4.0 3.3 0.2 0.1 Interest cost17.2 17.3 3.9 3.9 Plan amendments— 1.1 — — Actuarial (gain) loss(3.2)11.0 0.3 4.8 Medicare Part D— — 0.2 0.3 Acquisition— 28.6 — 0.8 Benefits paid