How we worked it out
Updated as you change the numbers.
- Work out each partner’s tax as a single filer and add them; then work out the couple’s tax on their combined income filing jointly; compare.
Method and assumptions
For most brackets the joint thresholds are exactly double the single ones, so couples with different incomes usually get a bonus and couples with similar incomes break even. Penalties appear mainly at the top (the 35% and 37% joint thresholds are less than double) and through credits and deductions not modeled here.
Questions
Do couples pay more tax when they marry?
Usually not at the federal level: with incomes of $120,000 and $40,000 the couple saves about $2,650 filing jointly. Penalties are most common when both earn high, similar incomes.
Sources
- IRS Revenue Procedure 2025-32 (2026 inflation adjustments), sections 4.01 and 4.15
- IRS IR-2025-103: inflation adjustments for tax year 2026
- IRS Publication 15 (2026) and Topic 751: Social Security wage base and rates
- IRS Topic 560: Additional Medicare Tax
Method and figures checked on . Every worked answer on this page is covered by an automated test. Found a mistake? Tell us.