v3.26.1
Debt
 3 Months Ended
Mar. 31, 2026
Debt Disclosure [Abstract]  
Debt Debt
Our outstanding borrowings at March 31, 2026 and December 31, 2025 consisted of the following:
(Millions of dollars)March 31,
2026		December 31,
2025
MPC:
Senior notes$6,449 $6,449 
MARAD debt154 161 
Finance lease obligations663 689 
Total7,266 7,299 
MPLX:
Senior notes26,000 26,000 
Finance lease obligations6 6 
Total26,006 26,006 
Total debt33,272 33,305 
Unamortized debt issuance costs(214)(204)
Unamortized discount, net of unamortized premium(233)(225)
Amounts due within one year(2,119)(2,371)
Total long-term debt due after one year$30,706 $30,505 

MPLX Senior Notes
On February 12, 2026, MPLX issued $1.0 billion aggregate principal amount of 5.300 percent senior notes due 2036 (the “2036 Senior Notes”) and $500 million aggregate principal amount of 6.100 percent senior notes due 2056 (the “2056 Senior Notes”) in an underwritten public offering. The 2036 Senior Notes were offered at a price to the public of 99.678 percent of par, with interest payable semi-annually in arrears, commencing on October 1, 2026. The 2056 Senior Notes were offered at a price to the public of 98.453 percent of par, with interest payable semi-annually in arrears, commencing on October 1, 2026.
In March 2026, MPLX repaid all of MPLX’s outstanding $1.5 billion aggregate principal amount of 1.750 percent senior notes due March 2026 at maturity.
Capacity under our Credit Facilities as of March 31, 2026
(Millions of dollars)Total
Capacity		Outstanding
Borrowings		Outstanding
Letters
of Credit		Available
Capacity		Weighted
Average
Interest
Rate		Expiration
MPC, excluding MPLX
MPC bank revolving credit facility$5,000 $— $1 $4,999 — %July 2027
MPC trade receivables securitization facility(a)
100 — 100 — — %September 2027
MPLX
MPLX bank revolving credit facility2,000 — — 2,000 — %July 2027
(a)    The committed borrowing and letter of credit issuance capacity under the trade receivables securitization facility is $100 million. In addition, the facility allows for the issuance of letters of credit in excess of the committed capacity at the discretion of the issuing banks. As of March 31, 2026, letters of credit in the total amount of $726 million were issued and outstanding under the facility to secure contracts awarded by the U.S. Department of Energy to purchase crude oil from the SPR.
On April 7, 2026, MPC and MPLX each entered into new revolving credit facilities to replace their respective previously existing credit facilities, which were scheduled to expire July 2027. The new facilities mature in April 2031. MPLX’s total capacity under the revolving credit facility increased from $2.0 billion to $2.5 billion, and includes sub-facilities for swing-line loans of up to $150 million and letters of credit of up to $150 million. MPC’s total capacity remains at $5.0 billion and includes sub-facilities for swing-line loans of up to $300 million and letters of credit of up to $2.0 billion.