In a recent letter, the Congressional Budget Office (CBO) estimates the One Big Beautiful Bill will increase budget deficits by $4.1 trillion over the fiscal year (FY) 2025–2034 budget window and push federal debt held by the public up to 127 percent of gross domestic product (GDP) by the end FY 2034. In a new insight, Director of Fiscal Policy Jordan Haring walks through the fiscal implications of the law with and without extensions of its provisions.

Key points:

• While some of the law’s provisions are temporary and will expire in several years, CBO estimates that if 10 of the temporary provisions were made permanent, the One Big Beautiful Bill would increase budget deficits by an additional $858 billion.
• Indeed, with extensions, that would bring the law’s total cost to $5 trillion, and the national debt would rise to 129 percent of GDP by the end of FY 2034.
• Of note, CBO’s projections are based on its January 2025 baseline and do not account for administrative actions related to tariffs and immigration and changes in economic conditions since then, and thus they are subject to a degree of uncertainty.

Read the analysis.