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💍 Penalty or bonus?

Marriage Tax Penalty Calculator

Does marriage raise or lower your tax bill? Enter both incomes to compare what you would pay as two single filers versus married filing jointly. When both spouses earn similar amounts, a marriage penalty often applies. When incomes are very different, you usually get a marriage bonus.

● 2026 brackets ● Single vs. MFJ ● FICA included

💍 Compare single vs. married

How it works

Marriage penalty vs. marriage bonus

The marriage penalty exists because the MFJ tax brackets are not perfectly double the single brackets at every level. When both spouses earn similar incomes, their combined income gets pushed into higher brackets faster under MFJ than it would as two separate single returns. Conversely, when one spouse earns much more than the other, the lower earner's income "fills up" the lower brackets that would otherwise be wasted, producing a bonus.

Who gets a penalty, who gets a bonus?

Income splitTypical result
50/50 (equal earners)Penalty (increases at higher incomes)
70/30Small penalty or breakeven
90/10 or 100/0Bonus (significant at higher incomes)
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For most couples under ~$400K combined: The 2026 brackets (10% through 32%) are exactly double for MFJ, so the penalty at these levels comes primarily from the FICA Additional Medicare Tax threshold ($250K MFJ vs. $200K single) rather than the brackets themselves. The real bracket penalty kicks in at the 35% and 37% levels.

Questions

Marriage tax penalty FAQ

What is the marriage tax penalty?

The marriage tax penalty occurs when a married couple filing jointly pays more federal income tax than they would have paid filing as two single individuals. It typically happens when both spouses earn similar incomes, because the MFJ brackets are not exactly double the single brackets at higher levels. The penalty was reduced by the Tax Cuts and Jobs Act but still exists for high earners.

When do married couples get a marriage bonus?

A marriage bonus happens when one spouse earns significantly more than the other (or when one has no income). The lower-earning spouse's income is effectively taxed at lower rates under MFJ because the wider brackets absorb it. Couples with very unequal incomes almost always receive a bonus.

Are the 2026 MFJ brackets exactly double the single brackets?

The 10%, 12%, 22%, 24%, and 32% brackets for MFJ are exactly double the single thresholds. The penalty starts at the 35% bracket, where MFJ caps at $512,450 vs. $256,225 single (exactly double), and the 37% bracket at $768,700 MFJ vs. $640,600 single (not double). Most of the penalty effects come from FICA and state tax interactions rather than the brackets themselves.

Does the marriage penalty affect FICA taxes?

FICA (Social Security and Medicare) is assessed per individual regardless of filing status, so there is no direct marriage penalty on FICA. However, the Additional Medicare Tax (0.9%) threshold is $200,000 for single filers but only $250,000 for MFJ — not double — which creates a small marriage penalty for high-earning couples.

Should we file jointly or separately?

Filing jointly almost always results in lower total tax than married filing separately (MFS). The MFS brackets are identical to single brackets, but MFS loses many deductions and credits. The rare exception is when one spouse has large medical expenses or student loan issues that benefit from a lower AGI threshold.

Mustafa Bilgic
Reviewed & maintained by
Mustafa Bilgic — Editor, SalaryCalculator.us

Brackets from IRS Rev. Proc. 2025-32.

  • Sources: IRS Rev. Proc. 2025-32 (2026 brackets, single and MFJ; standard deductions) · IRC Section 1(j) TCJA provisions.
  • 🔄 Last updated July 2026 · Tax year 2026

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