CBO Forecasts US Budget Deficit to Hit $1.9 Trillion, Pushing Debt-to-GDP Past 100% in 2026

The common assumption is that spikes in the federal deficit are driven primarily by new emergency spending or sudden economic downturns. However, the evidence reveals a different reality: the United States is entering a structural feedback loop where the cost of servicing existing debt is becoming the primary driver of new borrowing.[1]

According to the Congressional Budget Office's (CBO) "Budget and Economic Outlook: 2026 to 2036," the federal deficit will hit $1.9 trillion in fiscal year 2026. This represents roughly 5.8% of gross domestic product (GDP), a figure significantly higher than the 50-year historical average of 3.8%.[1]

The sheer volume of borrowing is pushing the national debt held by the public past a historic threshold. The CBO projects debt will rise from 101% of GDP in 2026 to 120% by 2036. This trajectory will eclipse the previous all-time record of 106%, which was set just after World War II.[1][6]

The data points to net interest payments as the fastest-growing segment of the federal budget. The CBO expects net federal interest payments to reach $1.0 trillion in 2026. By 2036, these costs are projected to approach $2.1 trillion, consuming 4.6% of GDP.[1][5]

This creates a compounding mathematical reality. As the American Action Forum's analysis of the CBO data highlights, the United States is approaching a stark crossover point: by fiscal year 2048, net interest payments are projected to eclipse spending on Social Security, making debt-servicing the single-largest government expenditure.[3]

The structural deficit is rooted in a persistent gap between what the government collects and what it spends. In 2026, federal outlays are projected to total $7.4 trillion, or 23.3% of GDP. Meanwhile, revenues will sit at $5.6 trillion, or 17.5% of GDP.[1]

While revenues are slightly above their 50-year average, outlays exceed their historical average by a widening margin. This spending growth is largely driven by mandatory programs for health and retirement, alongside the escalating interest on the debt.[1][6]

These projections carry transparent uncertainty, particularly regarding trade policy and administrative actions. The Bipartisan Policy Center notes that recent Supreme Court rulings invalidating certain tariffs have forced the Treasury to issue billions in unexpected customs refunds, expanding the near-term deficit.[2]

The CBO estimates that changes in trade policy through mid-2026 could add $0.9 trillion to deficits over the next decade. Furthermore, the baseline assumes current laws remain unchanged, meaning it does not account for the potential extension of the 2017 Tax Cuts and Jobs Act, which would significantly alter the revenue outlook.[1][2]

The bond market is already reacting to this fiscal deterioration. International Finance reports that long-term Treasury yields have risen sharply, with recent 10-year and 30-year bond auctions clearing at multi-decade highs.[4]

This market reaction reinforces the feedback loop: higher yields mean the government must pay more to refinance maturing debt, which in turn requires larger deficits. The approach of the $40 trillion total debt milestone is expected to test investor appetite for US Treasuries and bring the next debt-ceiling confrontation closer.[4]

International observers view these debt levels as a symptom of deeper political gridlock. Xinhua notes that while the US is not facing an imminent default—given its ability to issue debt in its own currency—the rising interest burden represents a massive drain on public resources that could otherwise fund infrastructure, education, and technology.[5]