Congressional Budget Office Final Score: Reconciliation Bill Increases Deficit by 3.4 Trillion; Causes 10 Million to Lose Health Insurance

This week, the Congressional Budget Office (CBO) released updated cost estimates of the recently enacted One Big Beautiful Bill Act (OBBBA), reflecting the final provisions. The score finds that between now and 2034, the law will add $3.4 trillion to the deficit and cause more than 10 million people to lose health insurance.

Although not reflected in the CBO report, an additional five million people are expected to become uninsured when the Affordable Care Act’s enhanced tax credits end later this year. Unlike other expiring tax breaks, the credits were not extended in the bill.

What’s in (and Not in) a Score?

The CBO and the Joint Committee on Taxation (JCT), both nonpartisan institutions working for Congress, are the official scorekeepers in Washington. They are charged with tallying the projected spending, revenue, deficit, and debt effects of legislation into a score.

Scores are not crystal balls—they cannot foretell all impacts a law will have on government spending and revenue with perfect accuracy. Importantly, they don’t attempt to predict or take into account future legal or legislative changes. Instead, they are the modeler’s best estimate for how the specific legislation will affect spending and revenue over a specified time period—usually 10 years.

The Comparator Is Key

In order to determine how a law will impact spending or revenue, it is critical to set a point of comparison, known as a “baseline,” relative to which the legislation’s changes and costs are measured. In the reconciliation bill, Republican lawmakers wanted to extend many of the policies from the 2017 Tax Creation and Jobs Act (TCJA) that were set to expire on December 31, 2025, including 3.8 trillion dollars in tax cuts. To do so, they used an accounting trick. They argued that, in evaluating the OBBBA, they could use a “current policy” baseline: comparing the world in which the law exists to one where the status quo in 2025 continued for 10 years. The problem with this approach is the fact that, absent legislative action, the 2025 status quo would not actually continue. So the “current policy baseline” was an inflated number, making the OBBBA appear to have a lower price tag.

Although a baseline built on this fiction was attractive to Republican lawmakers because it allowed them to continue the 2017 tax cuts without paying for them, ignoring reality doesn’t change it. The extended tax breaks do indeed come at a cost, exploding the deficit despite policymaker claims of fiscal responsibility. As experts at the Committee for Responsible Federal Budget note, “Many supporters of this law have spent months or years appropriately fuming about our unsustainable fiscal situation. But when they actually had an opportunity to fix it, they instead made it $4 trillion worse.”

As illustrated in the below chart created by the Bipartisan Policy Center, the two baseline accounting methods result in dramatically different estimates of the bill’s impact on the deficit. 

The latest CBO estimates confirm the OBBBA will have serious and long-lasting consequences. Alongside program cuts and coverage losses, the bill balloons the national debt. Doing so jeopardizes Medicare’s outlook by setting significant, automatic cuts in motion, and by creating a funding hole that lawmakers could use as an excuse to pursue even deeper cuts in the future. Both the new law and the dynamics it creates are unacceptable. Medicare Rights remains committed to minimizing and reversing these harms.

Read the CBO report.