Bonus Tax Calculator
Federal withholding on a bonus — percentage method vs. aggregate method, side by side.
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About the Bonus Tax Calculator
Estimates federal income-tax withholding on a bonus two ways — the flat 22%/37% percentage method most employers use for a bonus paid separately, and the aggregate method (bonus combined with a regular paycheck), which often withholds a different amount even though both are just prepayments toward your actual tax bill.
- Enter your bonus amount (before tax).
- If you've received other bonuses/commissions this calendar year, enter that running total — it affects whether you cross the $1,000,000 supplemental-wage threshold.
- Enter your regular gross pay per period and how often you're paid, so the aggregate-method estimate can be computed.
- Read both methods' estimated withholding, net bonus, and effective rate.
A $10,000 bonus with no prior supplemental wages this year, added to a $3,500 biweekly regular paycheck: the percentage method withholds a flat 22% ($2,200 federal withholding, $7,800 net). The aggregate method calculates a higher ~$2,958 (~29.6%) in this example — a real, commonly reported effect where the aggregate method can withhold more once a bonus pushes annualized income into a higher bracket.
| Cumulative supplemental wages this year | Federal withholding rate |
|---|---|
| Up to $1,000,000 | 22% |
| Amount above $1,000,000 | 37% |
Both methods are legitimate, IRS-permitted ways an employer can withhold federal income tax on a bonus — which one applies is the employer's choice, not yours. Neither number is your final tax bill: withholding is only a prepayment, reconciled against your actual full-year tax liability when you file (see the W-4 Withholding Calculator). This tool covers federal income tax withholding only — FICA is still withheld on a bonus at normal rates, and state/local withholding isn't modeled. Not tax advice.
- • If your bonus is paid on a separate check from your regular pay, ask your payroll department which method they use — it changes what's withheld from that specific check, not your actual year-end tax bill.
- • A big withholding hit on a bonus isn't necessarily "extra tax" — if your effective full-year tax rate is lower than what was withheld, you'll get the difference back as part of your refund.
- • The aggregate method tends to withhold more than the percentage method when a bonus is large relative to your regular paycheck.
- IRS Publication 15 (Circular E) — Employer's Tax Guide — accessed 2026-08-30
- IRS — Publication 15-T, Federal Income Tax Withholding Methods — accessed 2026-08-30
Illustrative estimate only, not financial or tax advice. Verify figures with a licensed adviser or your local tax authority.