U.S. Debt Doubles Under Trump and Biden — Now Exceeds $40 Trillion

The odometer flipped on August 19. That morning, Treasury reported $40.047 trillion in total public debt outstanding, the first time the federal balance sheet has ever begun with a four. The pace of the accumulation is what should stop readers. It took the United States until 1981 to reach $1 trillion in debt for the first time. It took less than five months to go from $39 trillion to $40 trillion. The last trillion was added in roughly the time it takes to close on a house.

Two Presidents, One Ledger

The tally is bipartisan and it is not close. Federal debt has risen by $11.6 trillion across Donald Trump’s two terms, including $3.8 trillion since January 2025, and by $8.4 trillion during Joe Biden’s four-year term. About a third of the combined increase came from pandemic-era borrowing under both administrations. The rest came from the ordinary math of an aging population, permanent tax cuts, and defense budgets that only ratchet up.

The composition of federal spending explains why the trajectory is hard to bend. Washington now spends roughly $7 trillion a year, with 60% of it locked into mandatory programs like Social Security, Medicare, and Medicaid. Discretionary appropriations, the part Congress actually votes on each year, are the minority of the budget.

Interest Is Now the Second-Biggest Bill

The most consequential line item is the one Congress never debates. Interest on the debt has climbed to $1.1 trillion, the second-largest expense in the federal budget after Social Security, exceeding Medicare outlays for the first time in the first 10 months of fiscal 2026. Fortune reported this week that annualized interest payments have since climbed to $1.25 trillion.

The Treasury yield curve is why. On September 9, the 10-year Treasury yielded 4.83% and the 30-year yielded 5.28%, both meaningfully above the 3.75% federal funds upper bound that the Federal Reserve set after three cuts from 4.5% in September 2025. Every time an old, low-coupon Treasury matures, it is refinanced at these higher rates. The Fed can cut all it wants at the short end; the long end is where the debt actually lives.

Growth is not bailing anyone out. Real GDP expanded at just 1.5% in the second quarter of 2026, below the 2% to 3% trend range the Bureau of Economic Analysis considers healthy. Meanwhile, foreign investors, who hold nearly a third of Treasuries, have reduced their demand over the past year.

Why It Reaches Your Kitchen Table

Maya MacGuineas of the Committee for a Responsible Federal Budget warned that the debt “doesn’t exist solely on the government’s ledgers” but is “felt throughout the economy” through inflation, squeezed priorities, and reduced emergency capacity. KPMG chief economist Diane Swonk put the transmission mechanism more bluntly on Marketplace, saying the cost of the debt is “pushing up interest rates on everything from auto loans to buying a new home, which has just now hit a new affordability threshold.”

Watch two things this fall. First, the Treasury’s quarterly refunding announcement in early November, which will show how aggressively the department is leaning on short-term bills to avoid locking in 5%-plus long rates. Second, the fiscal-year-end interest tally: if it prints above $1.25 trillion, interest expense will have grown faster than any other category of federal spending for a third straight year. That is the number that decides whether $40 trillion becomes a headline or a hinge.

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