How much do new tax cuts boost consumer spending and GDP?
Core argument: OBBBA's new provisions are projected to cut household income taxes by roughly $220 billion in 2026, equal to 0.7% of GDP.
The total reduction in household income taxes in 2026 from OBBBA's new provisions will be roughly $220 billion, or 0.7% of GDP, with a bit more than half of the boost to after-tax income coming from retroactive changes for 2025 and the rest coming from the changes to withholding tables for 2026 paychecks. Relying on the broad research literature on the marginal propensity to consume, we ultimately expect the reduction in household income taxes to boost consumer spending by roughly $90 billion this year. This translates to a boost of around 0.3% to 2026 GDP.

