How Does Bonus Pay Affect Paycheck Withholding?
By Onoir Studio LimitedPublished Source links reviewed
A bonus is generally taxable wages, but the federal income tax taken from the check is only withholding. It is not a separate “bonus tax” or necessarily the final tax attributable to that payment.
Key takeaways
- The IRS treats bonuses as supplemental wages.
- For qualifying separately identified supplemental wages in 2026, an employer may use a flat 22% federal income tax withholding method.
- Another permitted method combines or aggregates the bonus with regular wages, which can make withholding look higher.
- Social Security, Medicare, state, local, and benefit deductions may apply in addition to federal income tax withholding.
Federal bonus withholding methods for 2026
IRS Publication 15 lists bonuses among supplemental wages. If a bonus is paid with regular wages and the amounts are not separately identified, the employer generally withholds as though the total were one regular payroll payment.
When a bonus is separately identified and the IRS conditions are met, an employer may use the optional flat 22% method or an aggregate method that combines supplemental and regular wages for a payroll-period calculation and subtracts tax already withheld. The employer chooses a permitted method; an employee generally cannot require the flat method.
If supplemental wages paid by an employer to one employee exceed $1 million during the calendar year, the excess is subject to mandatory 37% federal withholding for 2026 under Publication 15. Special aggregation rules can apply to businesses under common control.
A $5,000 bonus example
Assume a separately paid $5,000 bonus qualifies for the flat method, the employee remains below the 2026 Social Security wage base, and no Additional Medicare Tax, state tax, local tax, or benefit deduction applies.
| Item | Calculation | Amount |
|---|---|---|
| Federal income tax withholding | $5,000 × 22% | $1,100.00 |
| Employee Social Security | $5,000 × 6.2% | $310.00 |
| Employee Medicare | $5,000 × 1.45% | $72.50 |
| Illustrative payment after listed items | $5,000 − $1,482.50 | $3,517.50 |
The IRS states that the 2026 Social Security employee rate is 6.2% up to the $184,500 wage base and the Medicare employee rate is 1.45% with no wage-base limit. Employers also begin withholding 0.9% Additional Medicare Tax after wages paid to an employee exceed $200,000 in the calendar year. Individual tax liability uses different thresholds and filing-status rules.
Why a bonus can look “taxed more”
A bonus check can show several deductions at once. The aggregate method may temporarily project the combined payment across a regular pay period, while the flat method starts with 22% federal withholding before payroll taxes. State or local supplemental-wage rules may add withholding, and retirement-plan elections or other deductions may apply to bonus pay under plan terms.
At filing time, federal income tax is generally calculated on annual taxable income. Federal withholding from the bonus and regular wages is credited against that total. Depending on total income, deductions, credits, filing status, and all payments, the bonus withholding may be too high, too low, or close to the ultimate result.
How to review a bonus paycheck
- Confirm the gross bonus and whether it was separately identified.
- Separate federal income tax withholding from Social Security and Medicare.
- Check year-to-date Social Security wages against the current wage base.
- Identify state and local withholding and any retirement or benefit deductions.
- Use the IRS Tax Withholding Estimator with complete annual income information if you are considering a Form W-4 change.
A W-4 change affects future withholding and should reflect the full household tax picture, not just the appearance of one bonus check.
Where this comes from
- IRS Publication 15 (2026), Section 7: Supplemental Wages (opens in a new tab)
- IRS Publication 15-T (2026), Federal Income Tax Withholding Methods (opens in a new tab)
- IRS Topic 751: Social Security and Medicare Withholding Rates (opens in a new tab)
- IRS Tax Withholding Estimator (opens in a new tab)
Want an estimate for your own job? The calculator applies its model to your hourly rate, hours and state.
Open the calculator