Accurate Budgeting Act - Amends the Congressional Budget Act of 1974 to require the Joint Committee on Taxation to prepare for each major revenue bill or resolution, reported by specified congressional tax committees or considered on the floor of either chamber, as a supplement to Congressional Budget Office (CBO) cost estimates, a macroeconomic impact analysis of the budgetary effects of the legislation for: (1) the 10-fiscal year period beginning with the first fiscal year for which such estimate was prepared, and (2) each of the next three 10-fiscal year periods.

Defines "major revenue bill or resolution" as a bill, resolution, or conference report for which either:

• the sum of the positive changes in revenues resulting from such measure (not including the impact of any timing shifts for the due date for estimated corporate income tax payments) for any fiscal year in the period for which a CBO cost estimate is prepared, or
• the absolute value of the sum of the negative changes in revenues resulting from such measure,

is greater than 0.25% of the current projected U.S. gross domestic product (GDP) for that fiscal year.