US federal debt stood at $40.55 trillion on Oct. 28, with the total covering debt held by the public and intragovernmental holdings, the Treasury Department said.
The total rose $448.9 billion, or 1.1%, from Sept. 28. It increased $2.47 trillion, or 6.5%, from Oct. 28, 2025, putting the annual dollar increase above the monthly change.
Debt held by the public accounted for $32.67 trillion of the outstanding balance. Intragovernmental holdings accounted for the other $7.88 trillion, the department said.
The public holdings made up the larger part of federal debt at the October recording date. Both categories were included in the $40.55 trillion total, rather than representing amounts in addition to it.
Accrued interest expense totaled $63.1 billion in September, the latest month supplied, and $800 billion for fiscal year 2026 to date. The department recorded those figures for Sept. 30.
The interest figures therefore covered an earlier period than the outstanding debt balance. The September expense measured interest accrued that month, while the fiscal-year figure covered the cumulative amount for fiscal year 2026.
Treasury notes accounted for the largest interest expense among the categories listed, at $43.5 billion in September. Their fiscal-year expense totaled $498.3 billion, also the largest amount among those categories.
Treasury bonds followed with $15.3 billion in accrued interest for September and $178.2 billion for the fiscal year to date. Both amounts were below the corresponding expenses for Treasury notes.
Interest expense from inflation compensation on Treasury Inflation-Protected Securities, known as TIPS, was negative $452 million in September. The same category recorded a positive $69.7 billion for the fiscal year to date.
That category had the third-largest fiscal-year interest expense among those listed, behind notes and bonds. Its negative monthly amount contrasted with the positive September expenses in each of the other supplied categories.
Treasury floating rate notes accounted for $2.3 billion in September interest expense. The cumulative expense for those securities reached $26.7 billion for fiscal year 2026 to date.
A separate category for inflation-protected securities recorded $2.1 billion in monthly interest expense and $24.4 billion for the fiscal year. Those amounts were separate from the inflation-compensation figures.
State and local government certificates of indebtedness, notes and bonds accounted for $218.9 million in September interest expense. Their fiscal-year expense totaled $2.7 billion, the smallest cumulative amount among the categories supplied.