Supplemental wage and bonus tax calculator.
Estimate federal supplemental wage withholding for bonuses, commissions, severance, and gross-up payments using 2026 federal payroll rates. Include FICA, Additional Medicare Tax, and optional state or local rates.
Use the calculator Read the withholding guideCalculator inputs
What this calculator estimates
This page is designed for quick planning and payroll study. It focuses on separately stated supplemental wages, not full regular-paycheck withholding.
22% and 37% supplemental rates
Estimates the optional 22% federal flat rate under the $1 million threshold and 37% withholding on excess supplemental wages.
Social Security and Medicare
Applies the 2026 Social Security wage base and regular Medicare rate when employee FICA is included.
Additional Medicare Tax
Estimates the 0.9% employee Additional Medicare Tax once wages paid by the employer exceed $200,000.
Gross-up mode
Estimates the gross supplemental payment needed to produce a target net amount after modeled taxes and deductions.
How to interpret the result
The 22% supplemental wage rate is a federal income tax withholding rate, not a final tax rate. An employee’s final income tax depends on the full tax return, filing status, annual income, deductions, credits, and other withholding.
For a full payroll calculation, employers also need to consider regular wages, Form W-4, pre-tax deductions, state and local requirements, wage bases, benefits, garnishments, and payroll system setup.
Calculator FAQ
Are bonuses taxed at 22%?
Not exactly. The 22% rate is an optional federal withholding rate for certain supplemental wage payments under the $1 million threshold. It is not necessarily the employee’s final income tax rate.
Does this calculator model the aggregate method?
No. The aggregate method depends on regular wages and the employee’s Form W-4 withholding calculation. This calculator focuses on the supplemental flat-rate method and simple manual-rate modeling.
Does FICA apply to supplemental wages?
Generally yes, if the payment is wages subject to FICA. Social Security applies up to the annual wage base, regular Medicare has no wage base, and Additional Medicare Tax may apply after the employer withholding threshold is crossed.
What is a gross-up?
A gross-up estimates the gross payment needed so the employee receives a target net amount after modeled withholding and deductions.
Can I use this for state withholding?
You can enter a simple flat state or local estimate, but state and local supplemental wage rules vary. Verify the actual rules for the employee’s work and tax location.
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