How large will federal deficits and debt grow over the decade?
Core argument: CBO projects the federal deficit will rise from $1.9 trillion in fiscal year 2026 to $3.1 trillion in 2036, equal to 5.8% of GDP growing to 6.7%, compared with the 3.8% average of the past 50 years.
In CBO’s projections, the federal budget deficit in fiscal year 2026 is $1.9 trillion and grows to $3.1 trillion by 2036. Relative to the size of the economy, the deficit is 5.8% of gross domestic product (GDP) in 2026 and grows to 6.7% in 2036, which is greater than the 3.8% deficits averaged over the past 50 years. Rising net interest costs drive much of that increase. The primary deficit, which excludes those net interest costs, totals 2.6% of GDP this year and stays below that level through 2036, when it totals 2.1%. From 2026 to 2036, large and growing deficits cause debt to increase. Federal debt held by the public rises from 101% of GDP this year to 120 percent in 2036, surpassing its previous high of 106% of GDP in 1946.

