From CBO:

Each year, the Congressional Budget Office publishes a report presenting its projections of what the federal budget and the economy would look like over the next 30 years if current laws generally remained unchanged. The long-term budget projections typically follow CBO’s 10-year baseline budget projections and then extend most of the concepts underlying them for an additional 20 years. This year, the long-term projections are based on CBO’s May 2023 baseline projections but also reflect the estimated budgetary effects of the Fiscal Responsibility Act of 2023 (Public Law 118-5), which was enacted on June 3, 2023.

 

In CBO’s projections, the deficit equals 5.8 percent of gross domestic product (GDP) in 2023, declines to 5.0 percent by 2027, and then grows in every year, reaching 10.0 percent of GDP in 2053. Over the past century, that level has been exceeded only during World War II and the coronavirus pandemic. The increase in the total deficit results from faster growth in spending than in revenues. The primary deficit, which excludes interest costs, equals 3.3 percent of GDP in both 2023 and 2053, but the total deficit is boosted by rising interest costs.

 

By the end of 2023, federal debt held by the public equals 98 percent of GDP. Debt then rises in relation to GDP: It surpasses its historical high in 2029, when it reaches 107 percent of GDP, and climbs to 181 percent of GDP by 2053. Such high and rising debt would slow economic growth, push up interest payments to foreign holders of U.S. debt, and pose significant risks to the fiscal and economic outlook; it could also cause lawmakers to feel more constrained in their policy choices.