See whether getting married raises or lowers your federal income tax. Compare filing jointly versus two single filers using 2025 tax brackets to find your marriage penalty or bonus.
Penalty or bonus (2025 brackets)
Marrying can change your federal income tax. A marriage bonus happens when filing jointly results in less total tax than the couple would pay as two singles — common when one spouse earns much more than the other. A marriage penalty happens when filing jointly costs more, which can occur when two high, similar incomes get pushed into higher brackets together. This calculator computes both scenarios using 2025 federal brackets and the standard deduction ($15,000 single, $30,000 married filing jointly) and shows the difference.
For most middle-income couples with unequal incomes, marriage produces a modest bonus. The penalty mainly affects two high earners with similar incomes, because the top brackets for joint filers are not exactly double the single brackets. Note this estimate covers federal income tax only — it uses the standard deduction and excludes credits, state taxes, and other adjustments.
Usually occurs with unequal incomes — the lower earner's income is taxed in the couple's lower joint brackets, cutting total tax.
Mostly affects two similar high incomes, where the joint brackets aren't double the single ones at the top, raising total tax.
Uses 2025 federal rates (10%–37%) and standard deductions. Federal income tax only — excludes credits and state tax.
Marriage changes federal tax because filing jointly merges two incomes into one bracket structure. Whether that helps or hurts depends almost entirely on how similar the two incomes are. Joint brackets are exactly double the single brackets up to the 32% band, so two people earning identical salaries see no change at all — the "penalty" that dominates popular discussion only bites at high incomes where the joint bands stop doubling. Unequal earners, by contrast, get a genuine bonus: the higher earner's income is effectively averaged down into the lower earner's unused lower brackets.
Bonus or penalty = (Tax as two singles) − (Tax filing jointly)Joint thresholds = 2 × single thresholds up to the 32% bracketJoint standard deduction = $30,000 (2026)where:
Assumptions: Federal only. State treatment, phase-outs of credits, and the loss of certain filing-separately options can all shift the result, and student-loan income-driven repayment plans sometimes make filing separately cheaper overall.
Two couples with the same $190,000 household income and opposite outcomes.
ResultEqual earners: no change. Unequal earners: a $581 bonus
The pattern generalises — the more unequal the two incomes, the larger the bonus, because more of the higher salary is pulled down into unused low brackets. A single-earner couple gets the largest bonus of all. Penalties appear mainly above $500,000, where joint bands stop doubling.