Is there a marriage tax penalty for us?

How it works

The calculator fills in three 2026 federal returns, each with wages as the only income and the standard deduction:

• Your unmarried return: single, or head of household when you have a child under 17 living with you; your wages and your children.
• Your partner's unmarried return: the same rule with their wages and children.
• The married return: married filing jointly, with both wages and all the children.

Each return:

1. Taxable income = wages − standard deduction ($16,100 single, $24,150 head of household, $32,200 joint), not below $0.
2. Tax: below $100,000 of taxable income, the Tax Table, which is the rate schedule at the middle of the table row, rounded to whole dollars. The rows are $50 wide from $3,000 and $25 wide from $25 to $3,000; below $25 they are $0 to $5, $5 to $15 and $15 to $25. At or above $100,000, the rate schedule.
3. Child tax credit: $2,200 per child under 17, less $50 for each $1,000 (or part) of wages over $200,000 ($400,000 joint); first against the tax, then the refundable part, the smaller of what is left, $1,700 per child, and 15% of wages over $2,500. With 3 or more children, the 15% figure becomes the larger of itself and the Social Security and Medicare tax withheld less the earned income credit (Schedule 8812 Part II-B). The page takes that withheld tax as 6.2% of wages up to $184,500, plus 1.45% of wages, plus 0.9% of wages over $200,000. With wages as the only income, Part II-B changes the result only below $1 of wages, where the earned income credit is $0.
4. Earned income credit, from the IRS EIC Table amounts for the number of children (up to 3), using the joint phase-out on the married return.
5. Additional Medicare Tax: 0.9% of wages over $200,000 ($250,000 joint).
6. Tax after credits = tax − child tax credit + Additional Medicare Tax − refundable child credit − earned income credit (below $0 is a refund beyond withholding).

Change from marrying = married tax − (your unmarried tax + your partner's unmarried tax). The result uses the change as shown, rounded to the cent: $0.00 is no change, above $0.00 a marriage penalty, below $0.00 a marriage bonus. So a change of +$0.0008 shows $0.00 and "No change".

Figures that change each year

These figures live in the shared 2026 federal tax dataset of the site's tax engine (src/sdk/tax/data/federal-2026.ts). The data check should compare them with the next year's IRS revenue procedure.

When the data is out of date

After April 15, 2027 the page keeps using the 2026 tables and says so above the result.

Assumptions

• Tax year 2026; wages are the only income; standard deduction on every return. With no qualifying child, the earned income credit needs an age of 25 to 64; each partner is taken to meet it.
• An unmarried partner with a child under 17 files as head of household and claims that child; married, the couple claims all the children.
• State tax is not included. An estimate, not tax advice.

Worked examples by hand

$80,000 and $40,000, no children. Single: taxable 63,900, row middle 63,925: 1,240 + 4,560 + 22% × 13,525 = 8,775.50, so $8,776; taxable 23,900, row middle 23,925: 1,240 + 12% × 11,525 = $2,623. Joint: taxable 87,800, row middle 87,825: 2,480 + 12% × 63,025 = $10,043. Change = 10,043 − 11,399 = −$1,356, a bonus.

$60,000 each. Single: taxable 43,900, row middle 43,925: 1,240 + 12% × 31,525 = $5,023 each, $10,046 together; joint $10,043. Change = −$3, Tax Table rounding.

$300,000 each. Single: taxable 283,900: 58,448 + 35% × 27,675 = 68,134.25, plus 0.9% × 100,000 = 900: $69,034.25 each. Joint: taxable 567,800: 116,896 + 35% × 55,350 = 136,268.50, plus 0.9% × 350,000 = 3,150: $139,418.50. Change = +$1,350, all from the Additional Medicare Tax.

$700,000 each. Single: taxable 683,900: 192,979.25 + 37% × 43,300 = 209,000.25, plus 0.9% × 500,000 = 4,500: $213,500.25 each. Joint: taxable 1,367,800: 206,583.50 + 37% × 599,100 = 428,250.50, plus 0.9% × 1,150,000 = 10,350: $438,600.50. Change = +$11,600.

A single parent of two, $40,000, and a partner with $40,000. Parent, head of household: taxable 15,850, row middle 15,875: $1,588; child credit 4,400 covers it, and the refundable part is the smaller of 2,812, 3,400 and 15% × 37,500 = 5,625: $2,812; earned income credit at the $40,000 row: 7,316 − 21.06% × (40,025 − 23,890) = 3,917.97, so $3,918. Tax after credits = 1,588 − 1,588 − 2,812 − 3,918 = −$6,730. Partner: $2,623. Joint: taxable 47,800, row middle 47,825: 2,480 + 12% × 23,025 = 5,243, less 4,400 of child credit = $843 (no earned income credit at $80,000). Change = 843 − (−4,107) = +$4,950.