The United States has crossed the $40 trillion national debt mark for the first time, highlighting the scale of Washington's fiscal imbalance and the growing cost of servicing federal borrowing.

US Treasury data showed total public debt outstanding at $40.047 trillion on Tuesday. Of that amount, $32.266 trillion was held by the public, while $7.782 trillion was classified as intragovernmental holdings.

The debt has more than doubled since Donald Trump first entered the White House in January 2017, when it stood at about $19.95 trillion.

Pandemic Changed The Trajectory

The sharpest acceleration came during the Covid-19 pandemic, when Washington approved trillions of dollars in emergency assistance for households, businesses, healthcare systems and state governments.

Those programmes helped cushion the economic shock, but federal borrowing remained elevated after the pandemic emergency ended. Spending continued across healthcare, defence, infrastructure and other federal programmes while government revenue remained insufficient to cover total expenditure.

Debt therefore continued to rise under successive administrations rather than being driven by a single president or policy.

Deficits Keep Growing

At the heart of the problem is the persistent gap between what the federal government spends and what it collects in taxes and other revenues.

The US Treasury reported a $432 billion budget deficit in July alone. During the first 10 months of fiscal 2026, the government had already recorded a deficit of about $1.8 trillion, exceeding the entire deficit accumulated during fiscal 2025.

Social Security, Medicare, Medicaid and other mandatory programmes account for a large portion of federal spending. An ageing population and rising healthcare costs are putting additional pressure on these programmes.

Tax Cuts Add Pressure

Tax policy has also contributed to the long-term fiscal gap.

Successive tax reductions have limited the growth of federal revenues, while spending commitments have remained high. Reuters reported that debt increased by about $7.8 trillion during Trump's first term, including the pandemic period, and by another $8.4 trillion during Joe Biden's presidency. Since Trump returned to office in January 2025, debt has increased by a further $3.8 trillion.

The figures underline the bipartisan nature of America's borrowing problem.

Interest Bill Gets Bigger

Rising debt is creating another problem: the government must spend increasingly more simply to service existing borrowing.

Net interest on publicly held federal debt reached $963 billion during the first 10 months of fiscal 2026, according to the Congressional Budget Office figures cited in recent reporting. That works out to more than $3 billion a day.

Reuters reported that annual interest costs have risen to around $1.1 trillion. Interest payments have also overtaken Medicare spending, becoming the second-largest federal expenditure after Social Security.

Markets Watch Closely

The $40 trillion milestone comes as investors are paying closer attention to America's borrowing requirements and Treasury yields.

Higher government borrowing can put upward pressure on interest rates, particularly when investors demand greater returns to hold longer-term government bonds. That can eventually influence mortgage rates, business borrowing costs and other financing conditions.

The Treasury has also announced larger purchases of longer-dated bonds, a move that recently contributed to a decline in long-term yields.

For financial markets, the central concern is whether Washington can stabilise borrowing without sharply reducing economic growth.

What Happens Next

The US debt trajectory will depend on decisions over taxation, mandatory spending, defence, healthcare and interest costs. The challenge is becoming more difficult because higher debt itself increases the amount of money required to service existing obligations.

The latest milestone does not mean the United States faces an immediate default. However, it highlights a widening structural problem that has accumulated across administrations.

With the US national debt now above $40 trillion and federal borrowing projected to remain above $2 trillion for the current fiscal year, pressure on Washington to address the deficit is likely to intensify.