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Marriage Tax Compare
Enter both incomes and the effective rates you want to test. The calculator applies flat rates to each income and to the combined income so the direction of the difference is visible.
Real tax systems use brackets, allowances and caps, so a flat-rate comparison can be wrong in both direction and size. Use it to frame the question, then check the official rules or an accountant. This is budgeting information, not tax or legal advice.
What the comparison shows
The difference comes from applying one rate to two incomes versus a joint rate to the combined income. If the married rate is lower than the weighted single rates, the couple shows a saving; if higher, a penalty.
Social contributions are applied at the same rate in both scenarios so the comparison isolates the income tax assumption. Real contribution bases and caps differ.
Why flat rates mislead
Brackets mean the effective rate changes with income, and marriage can move income between brackets. Allowances, credits and filing status rules add further differences.
Use the result as a first question for an accountant: does joint filing help or hurt at our incomes? The answer depends on the jurisdiction and the year.
Frequently asked questions
Is this a tax return?
No. It is a flat-rate comparison built from the rates you enter, with no brackets, credits or allowances.
Should social contributions be included?
Include them if they change between filing statuses. In many systems they do not, which is why the same rate is applied to both scenarios.
Can marriage increase tax?
In some systems and income combinations, yes. That is often called a marriage penalty.