Budget reconciliation is a special parliamentary procedure of the United States Congress set up to expedite the passage of certain budgetary legislation in the United States Senate. The procedure overrides the filibuster rules in the Senate, which may otherwise require a 60-vote supermajority for passage by the Senate. Bills described as reconciliation bills can pass the Senate by a simple majority of 51 votes or 50 votes plus the Vice President's as the tie-breaker. The reconciliation procedure also applies to the House of Representatives, but it has minor significance there, as the rules of the House of Representatives do not have a de facto supermajority requirement. Due to greater polarization, gridlock, and filibustering in the Senate in recent years, budget reconciliation has come to play an important role in how the United States Congress legislates.

Budget reconciliation bills can deal with spending, revenue, and the federal debt limit, and the Senate can pass one bill per year affecting each subject. Congress can thus pass a maximum of three reconciliation bills per year, though in practice it has often passed a single reconciliation bill affecting both spending and revenue. Policy changes that are extraneous to the budget are limited by the "Byrd Rule", which also prohibits reconciliation bills from increasing the federal deficit after a ten-year period or making changes to Social Security.

In April 2021, the Senate Parliamentarian—an in-house rules expert—determined that the Senate can pass two budget reconciliation bills in 2021: one focused on fiscal year 2021 and one focused on fiscal year 2022. In addition, the Senate can pass additional budget reconciliation bills by describing them as a revised budget resolution that contains budget reconciliation instructions. However, the Parliamentarian later clarified that the “auto-discharge” rule that allows a budget resolution to bypass a Budget Committee vote and be brought directly to the Senate floor does not apply to a revised budget resolution. As a result of this ruling, a revised budget resolution would need to be approved by a majority vote of the Budget Committee before proceeding to the Senate floor, or deadlocked with a tied vote and then brought to the Senate floor via a motion to discharge. In a 50-50 Senate where committees are evenly divided between parties, this has the functional effect of requiring at least one member of the minority party on the Budget Committee to be present in order to provide a quorum for a vote. Considering the inherently partisan nature of reconciliation legislation, it is highly unlikely that a member of the minority party will cooperate with the majority by providing a quorum on the Committee, thus practically limiting the majority of a 50-50 tied Senate to one reconciliation bill per fiscal year.

The reconciliation process was created by the Congressional Budget Act of 1974 and was first used in 1980. Bills passed using the reconciliation process include the Consolidated Omnibus Budget Reconciliation Act of 1985, the Personal Responsibility and Work Opportunity Act of 1996, the Economic Growth and Tax Relief Reconciliation Act of 2001, the Health Care and Education Reconciliation Act of 2010, the Tax Cuts and Jobs Act of 2017, the American Rescue Plan Act of 2021, and the Inflation Reduction Act of 2022.