Total US public debt outstanding stood at $40.53 trillion on Oct. 26, with the balance covering debt held by investors and holdings within the government, the Treasury Department said.
The total rose $431.2 billion, or 1.1%, from Sept. 25, the comparison date for the change over about a month. It increased $2.49 trillion, or 6.5%, from Oct. 27, 2025.
Debt held by the public accounted for $32.64 trillion of the outstanding balance. Intragovernmental holdings, debt held within the federal government, accounted for the remaining $7.89 trillion.
The public-held portion was the larger of the two components that make up the federal debt total. Both components were recorded on Oct. 26, the date of the latest supplied debt balance.
Accrued interest expense, interest recorded as a cost as it builds up, totaled $63.1 billion in September, the Treasury Department said. The fiscal year-to-date total reached $800 billion for fiscal 2026.
The interest figures cover September and fiscal 2026, while the outstanding debt figures were recorded in October. The monthly interest amount therefore relates to an earlier period than the latest debt balance.
Treasury notes accounted for the largest interest expense among the categories supplied, both for September and for the fiscal year to date. Interest on notes totaled $43.5 billion for the month and $498.3 billion for fiscal 2026.
Treasury bonds were the next-largest category over both periods. Their interest expense totaled $15.3 billion in September, while the fiscal year-to-date amount was $178.2 billion.
Inflation compensation on Treasury Inflation-Protected Securities recorded negative interest expense of $452 million in September. The fiscal year-to-date amount for that category was positive at $69.7 billion, the third-largest fiscal-year expense among the categories supplied.
The separate interest category for Treasury Inflation-Protected Securities totaled $2.1 billion in September and $24.4 billion for the fiscal year to date. Those amounts were listed separately from the inflation compensation figures.
Treasury floating-rate notes accounted for $2.3 billion in September interest expense and $26.7 billion for fiscal 2026. That put their expense above the separate inflation-protected securities category for both the month and the fiscal year to date.
The category covering state and local government certificates of indebtedness, notes and bonds recorded $218.9 million in September interest expense. Its fiscal year-to-date expense totaled $2.7 billion, the smallest fiscal-year amount among the categories supplied.
