Bonus tax calculator
A bonus is supplemental wages, and the employer has two lawful ways to withhold federal income tax on it: a flat 22% rate, or folding the bonus into a regular paycheck and withholding on the total (the aggregate method). The two produce different cash today and the same tax bill in April, so this page shows both.
Year to date
The $1,000,000 threshold counts supplemental wages only. The FICA wage base counts all wages, which is why the two year-to-date fields are separate.
Withholding on the bonus
| Line | Flat 22% | Aggregate |
|---|
What counts as supplemental wages
Publication 15 defines them as wage payments that are not regular wages. The list is wider than most people expect, which is why the same rule governs commissions, severance and back pay:
"Supplemental wages are wage payments to an employee that aren’t regular wages. They include, but aren’t limited to, bonuses, commissions, overtime pay, payments for accumulated sick leave, severance pay, awards, prizes, back pay, reported tips, retroactive pay increases, and payments for nondeductible moving expenses.” IRS Publication 15 (2026), section 7
Method 1: the flat rate
If the bonus is paid separately from regular wages, the employer may withhold a flat 22%. The instruction is exact: no other percentage is allowed under this method. Once supplemental wages for the calendar year pass $1,000,000 in total, the excess is withheld at 37% without regard to the employee's Form W-4.
The flat rate is a withholding rate, not a tax rate. An employee whose marginal rate is 12% and whose bonus was withheld at 22% has overpaid during the year and gets the difference back at filing. An employee at 32% has underpaid and owes the rest in April.
Method 2: the aggregate method
The employer adds the bonus to the regular wages for the period, works out withholding on the total, and subtracts what was already withheld from the regular wages. The difference comes out of the bonus. This is what most payroll systems do when a bonus rides along with a normal paycheck, and it is why the bonus appears to be taxed at a higher rate: it is being withheld at your marginal rate instead of at a flat one.
Worked examples
Single filer, Texas (no state income tax), $3,000 of regular pay every two weeks. Every figure below is computed by the same engine that powers this page.
| Bonus | Flat: federal | Flat: FICA | Aggregate: federal | Aggregate: total withheld |
|---|---|---|---|---|
| $1,000.00 | $220.00 | $76.50 | $220.00 | $296.50 |
| $5,000.00 | $1,100.00 | $382.50 | $1,167.00 | $1,549.50 |
| $10,000.00 | $2,200.00 | $765.00 | $2,812.00 | $3,577.00 |
| $25,000.00 | $5,500.00 | $1,912.50 | $8,117.00 | $10,029.50 |
Recomputed at build time. Verified 2026-10-30.
Why FICA is never optional
Whichever income-tax method the employer uses, the bonus is subject to social security and Medicare. Social security stops at the annual wage base; Medicare does not, and the 0.9% additional Medicare tax starts at $200,000 of wages regardless of filing status. A large bonus can therefore cross two different thresholds at once, and they are measured against different year-to-date totals.
The rest of the supplemental bucket
Publication 15 puts bonuses, commissions, overtime and severance in the same category and gives them the same withholding rule. Each of these applies that rule to a different fact pattern:
- Overtime tax calculator - Overtime is supplemental wages. See the federal withholding, the FICA, and the net pay on an overtime payment,
- Severance pay tax calculator - Severance is supplemental wages: 22% flat withholding, 37% above $1M, and FICA on the whole amount. See the nu
State withholding is a separate question
States do not share one rule. Some publish a flat supplemental rate, some require the aggregate method, and some have no wage withholding at all. The table above shows a state line only for the aggregate method, because that is the method this page can compute from a state's own tables. Each state page states what that state requires.
Frequently asked questions
- Is a bonus taxed more than salary?
- No. A bonus is withheld differently, not taxed differently. Whatever is over-withheld during the year is refunded when you file, and whatever is under-withheld is owed then. The bonus and the salary land in the same taxable income.
- What rate is a bonus taxed at?
- Employers may withhold a flat 22% for federal income tax on supplemental wages, and must use 37% on the part of supplemental wages above $1,000,000 in a calendar year. Your actual tax rate is set by your bracket, not by this rule.
- Do I get the 22% back?
- If your marginal rate is below 22%, yes - the over-withholding shows up as a larger refund or a smaller balance due. If your marginal rate is above it, you owe the difference.
- Does FICA come out of a bonus?
- Yes, under either withholding method. Social security applies up to the annual wage base, Medicare applies with no cap, and the 0.9% additional Medicare tax starts at $200,000 of wages.
- Is overtime paid like a bonus?
- Publication 15 lists overtime pay as supplemental wages, but the employer may treat it as regular wages instead. That choice changes the withholding timing, not the tax.
- Why does the aggregate method withhold more?
- Because it withholds at your marginal rate rather than at a flat 22%. On a mid-size bonus for a mid-bracket employee the aggregate method usually withholds more today and leaves a smaller balance due in April.
- What about state tax on a bonus?
- States do not share one rule: some publish a flat supplemental rate, some require aggregation, and some have no wage withholding. The calculator shows a state line only for the aggregate method; the state pages cover what each state actually requires.
IRS Publication 15 (2026), section 7: supplemental wages, the 22% flat rate, the 37% rate above $1,000,000, and the rule that FICA applies either way.
IRS Publication 15-T (2026) for the withholding tables used by the aggregate method.
All figures verified on 2026-10-30.