Bonus Tax Calculator
See what actually gets withheld from your bonus using the IRS's flat supplemental-wage method — and why the check looks smaller than the number on paper.
How bonus withholding actually works
Plus: Social Security 6.2% (up to the annual wage base) + Medicare 1.45%
The IRS treats a bonus as a "supplemental wage" and allows employers to withhold federal income tax on it using a flat 22% rate, separate from your regular paycheck's withholding tables — this is called the Percentage Method, and it's what most employers use for bonuses paid separately from regular pay. Social Security and Medicare still apply the same way they do to any paycheck.
Federal withholding: $5,000 × 22% = $1,100. Social Security: $5,000 × 6.2% = $310. Medicare: $5,000 × 1.45% = $72.50.
Total withheld: $1,482.50 → take-home from the bonus: $3,517.50 (about 70.4% of the gross bonus).
Why 22% withholding isn't your final tax rate
This is the detail that confuses most people: 22% is just what gets withheld up front, not necessarily what you actually owe. Your real tax liability on that bonus depends on your total income for the year and where it falls in the federal bracket schedule. If your effective rate on that income turns out to be lower than 22% once you file your return, you get the excess back as part of your refund. If it's higher — for example, if the bonus pushes you into a higher bracket — you may owe more at filing time.
Common mistakes when estimating bonus withholding
- Assuming 22% is your permanent tax rate on that money. It's a withholding rate, not a final tax rate — the two are reconciled when you file.
- Forgetting the 37% rate on very large bonuses. Supplemental wages over $1,000,000 in a calendar year are withheld at 37% on the excess, not 22%.
- Not accounting for the aggregate method. Some employers combine the bonus with a regular paycheck and withhold using standard tables instead of the flat 22% — this can produce a different result than this calculator's Percentage Method assumption.
Frequently asked questions
Why is my bonus taxed so much higher than my regular paycheck?
It's withheld at a flat 22% regardless of your bracket — if your real rate is lower, you get the difference back at tax time.
Is the 22% bonus withholding rate the same as my actual tax rate?
No — it's a withholding estimate; your actual tax is determined by your total annual income when you file.
Does Social Security and Medicare tax apply to bonuses?
Yes — the same 6.2% and 1.45% rates apply as they do to regular wages.
Can my employer combine my bonus with a regular paycheck instead?
Yes — this "aggregate method" uses standard withholding tables instead of the flat 22% rate and can produce a different result.
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Note: Uses the IRS Percentage Method for supplemental wages; actual withholding may differ if your employer uses the aggregate method. Not tax advice. Figures: 2025 federal rates and wage base. Last reviewed: September 2026.