Marriage Tax Penalty Calculator

A marriage penalty happens when a couple pays more total federal income tax filing jointly than they would have paid as two single filers on the same incomes. A marriage bonus is the opposite, where filing jointly costs less. The size depends on how each spouse's income stacks against the tax brackets. Couples with two similar high incomes tend to see a penalty, while couples with one main earner tend to see a bonus.

It computes federal income tax three ways. First it taxes each spouse's taxable income on the Single brackets and adds the two results. Then it taxes the combined income on the Married Filing Jointly brackets. The difference, joint tax minus the two single taxes, is your penalty (a positive number) or bonus (a negative number). It uses the 2026 federal brackets.

Within this bracket-only 2026 model, the top-bracket thresholds create the displayed penalty for two high, similar incomes. A real return can also have marriage effects from deductions, credits, phaseouts, additional taxes, filing restrictions, and state law, none of which this calculator models.

A bonus is most common when one spouse earns much more than the other, or when one spouse has little or no taxable income. Filing jointly lets the lower earner's unused lower brackets absorb part of the higher earner's income, which drops the combined bill below two separate single returns. Enter 0 for a spouse with no taxable income to see this effect clearly.

Enter each spouse's taxable income, which is the amount left after the standard or itemized deduction, not gross salary. Using taxable income keeps the comparison clean, because the 2026 Married Filing Jointly standard deduction ($32,200) is exactly twice the Single deduction ($16,100) and does not create a penalty by itself. If you only know gross pay, subtract your deductions first.

No. This is an estimate for planning, not financial or tax advice. It models federal income tax brackets only and ignores state taxes, credits such as the Child Tax Credit, the additional Medicare tax, the Net Investment Income Tax, and phaseouts that can change the real result. Confirm your situation with a tax professional or the IRS before making decisions.