Debt and Credit Facility

3 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Debt and Credit Facility

6. Debt and Credit Facility

Senior Notes

At March 31, 2024 and December 31, 2023, we had outstanding fixed-rate unsecured Senior Notes with varying maturity dates. The stated interest rates and aggregate principal amounts of our Senior Notes were, respectively: (i) 4.625% and $500.0 million (“4.625% Senior Notes”) and (ii) 4.50% and $550.0 million (“4.50% Senior Notes”). Our Senior Notes do not require us to make any mandatory redemptions or sinking fund payments. The following table summarizes key details of our Senior Notes:

				Outstanding (in millions of dollars)
	Issuance Date	Maturity	Effective Interest Rate	As of March 31, 2024			As of December 31, 2023
4.625% Senior Notes	November 2019	March 2028	4.8%	$	500.0		$	500.0
4.50% Senior Notes	May 2021	June 2031	4.7%		550.0			550.0
Total debt					1,050.0			1,050.0
Unamortized issuance costs					(9.7	)		(10.2	)
Total carrying amount				$	1,040.3		$	1,039.8

The following table presents the fair value of our outstanding Senior Notes, which are Level 1 liabilities (in millions of dollars):

	As of March 31, 2024		As of December 31, 2023
4.625% Senior Notes	$	469.2	$	462.4
4.50% Senior Notes	$	486.6	$	474.1

Revolving Credit Facility

In October 2019, we entered into a Revolving Credit Facility. Joining us as borrowers under the Revolving Credit Facility are four of our wholly owned domestic operating subsidiaries: (i) Kaiser Aluminum Investments Company; (ii) Kaiser Aluminum Fabricated Products, LLC; (iii) Kaiser Aluminum Washington, LLC; and (iv) Kaiser Aluminum Warrick, LLC.

In April 2022, we entered into Amendment No. 3 to our Revolving Credit Facility. As amended, the Revolving Credit Facility contains a maximum commitment amount of $575.0 million (of which up to a maximum of $50.0 million may be utilized for letters of credit) and is set to mature in April 2027. Our effective interest rate on outstanding borrowings under the amended Revolving Credit Facility is based on the rates of Base Rate Loans and SOFR Loans (as defined in the amended Revolving Credit Facility). The rate for Base Rate Loans is equal to the prevailing Prime Rate plus 0.25%, while the rate for SOFR Loans, which are made for one or three month periods, is equal to the Term SOFR Reference Rate (as defined in the amended Revolving Credit Facility) plus 1.35%. Outstanding borrowings under the Revolving Credit Facility are reported within Long-term debt, net, on our Consolidated Balance Sheets. We had no borrowings under the Revolving Credit Facility during the quarter ended March 31, 2024. As of March 31, 2024 and December 31, 2023, we had no outstanding borrowings under our Revolving Credit Facility.

The following table summarizes availability and usage of our Revolving Credit Facility as determined by a borrowing base calculated as of March 31, 2024 (in millions of dollars):

Revolving Credit Facility borrowing commitment	$	575.0
Borrowing base availability	$	544.4
Less: Outstanding borrowings under Revolving Credit Facility		—
Less: Outstanding letters of credit under Revolving Credit Facility		(27.0	)
Remaining borrowing availability	$	517.4

Interest Expense

The following table presents interest expense relating to our Senior Notes and Revolving Credit Facility (in millions of dollars):

	Quarter Ended March 31,
	2024			2023
Senior Notes interest expense, including debt issuance cost amortization	$	12.4		$	12.4
Revolving Credit Facility interest expense, including commitment fees and finance cost amortization		0.6			0.8
Interest expense on finance lease liabilities		0.2			0.1
Interest expense capitalized as construction in progress		(1.7	)		(1.4	)
Total interest expense	$	11.5		$	11.9