Supplemental Wage Tax Calculator United States
This supplemental wage tax calculator estimates 2026 take-home pay on a bonus or commission after 22% flat withholding, 37% over $1M, FICA and state tax.
What it does
The Supplemental Wage Tax Calculator estimates the take-home value of supplemental wages in 2026 — bonuses, commissions, overtime, and severance — using the IRS flat-rate percentage method for federal withholding, plus FICA (Social Security and Medicare) and an optional flat state tax.
Data sources & parameters
The figures below drive this calculator. We keep them aligned with the latest official guidance, and each result recalculates automatically whenever a value changes.
| Parameter | Value | Source | Last updated |
|---|---|---|---|
| Federal supplemental wage withholding rate | 0.22 | irs.gov | Effective 2026-01-01Made open-ended (was valid to 2026-12-31): the 22% optional flat rate follows the permanent IRC 1 rate schedule (Treas. Reg. 31.3402(g)-1); unchanged for 2027. audit 2026-09-23 |
| Federal supplemental withholding rate above $1M | 0.37 | irs.gov | Effective 2026-01-01Made open-ended (was valid to 2026-12-31): the mandatory 37% rate over 1,000,000 follows the permanent top IRC 1 rate (Treas. Reg. 31.3402(g)-1); unchanged for 2027. audit 2026-09-23 |
| Cumulative supplemental wage cap for flat rate | 1,000,000 | irs.gov | Effective 2026-01-01Made open-ended (was valid to 2026-12-31): the 1,000,000 supplemental-wage threshold is fixed and not indexed (Treas. Reg. 31.3402(g)-1); unchanged for 2027. audit 2026-09-23 |
| Social Security (OASDI) employee rate | 0.062 | irs.gov | Effective 2026-01-01Made open-ended (was valid to 2026-12-31): the 6.2% OASDI rate is fixed by statute (IRC 3101(a)/3111(a)); unchanged for 2027. audit 2026-09-23 |
| Medicare employee rate | 0.0145 | irs.gov | Effective 2026-01-01Made open-ended (was valid to 2026-12-31): the 1.45% HI rate is fixed by statute (IRC 3101(b)(1)/3111(b)); unchanged for 2027. audit 2026-09-23 |
| Additional Medicare rate | 0.009 | irs.gov | Effective 2026-01-01Made open-ended (was valid to 2026-12-31): the 0.9% Additional Medicare Tax rate is fixed by statute (IRC 3101(b)(2)); unchanged for 2027. audit 2026-09-23 |
| Additional Medicare threshold | 200,000 | irs.gov | Effective 2026-01-01Made open-ended (was valid to 2026-12-31): the 200,000 threshold is fixed by statute and not indexed (IRC 3101(b)(2)); unchanged for 2027. audit 2026-09-23 |
| Social Security (OASDI) contribution and benefit base, 2026 | 184,500 | federalregister.gov, ssa.gov | Effective 2026-01-01Auto-update: replaced dead source link |
We always strive to use the latest data for every variable so our results and reports are as accurate as possible. Even so, errors are possible — you should not rely on this tool or its report alone, and we accept no liability for any decision made based on it.
The formula
Federal = amount up to the $1M cap × 22% + amount above the cap × 37%; FICA = amount × (6.2% + 1.45%); state = amount × state rate; net = amount − federal − FICA − state
How it works
It applies the flat federal supplemental rate to the payment up to a cumulative annual cap, switches to the mandatory higher rate on any portion above the cap, adds combined FICA, applies your state rate, and subtracts the total from the gross to show the cash you keep.
Where it is used
- Estimating the net cash from a bonus, commission, or overtime payment
- Checking the mandatory 37% withholding once yearly supplemental wages pass one million dollars
- Comparing take-home across different state tax rates
Worked example
A $10,000.00 supplemental payment has … withheld for federal tax and a total of … withheld once FICA and state tax are added, leaving a take-home of ….
Supplemental wages are extra payments on top of your salary, such as a year-end bonus, a sales commission, overtime or a severance package. The IRS lets employers withhold federal tax on them at a flat rate instead of running them through your normal payroll tables, and that rate is often higher than people expect. Enter the gross payment, your state rate and, optionally, the supplemental pay you have already received this year, and this supplemental wage tax calculator estimates the 2026 federal withholding, FICA and state tax, and your take-home amount.
What counts as a supplemental wage
The IRS defines supplemental wages as pay in addition to regular wages: bonuses, commissions, overtime, severance and back pay, payouts of accumulated sick or vacation leave, awards and prizes, and certain other one-off payments. Because these arrive irregularly and can be large, there is a separate withholding method so employers do not have to work out how one big payment interacts with your regular paychecks.
The flat percentage method
This calculator uses the percentage method, the most common approach. For 2026 the federal supplemental withholding rate is a flat 22% on the payment, so a $10,000 bonus has $2,200 withheld for federal income tax. Regular wages are withheld across brackets, but a bonus is withheld at one rate from the first dollar, which is why it can feel heavily taxed. For many middle earners the flat rate is close to their marginal rate; for lower earners it can be more than they owe, and the difference comes back as a refund.
The mandatory rate above one million dollars
Once your cumulative supplemental wages for the year pass one million dollars, the portion above that cap must be withheld at 37%, the top ordinary income rate, with no option to use the lower rate. A single $1.2 million payment with no earlier supplemental pay this year has the first one million withheld at 22%, or $220,000, and the remaining 200,000 at 37%, or $74,000, for $294,000 in total. Enter supplemental pay already received this year in the advanced field so the tool places the payment correctly against the cap.
FICA and state tax
Supplemental wages are also subject to FICA, the payroll tax for Social Security and Medicare. The combined employee rate is 7.65%: 6.2% for Social Security and 1.45% for Medicare. FICA is a tax, not withholding, so it is not refunded when you file. Social Security applies only up to an annual wage base, so high earners past the cap pay only the Medicare portion, and an Additional Medicare Tax can apply at high incomes. Most states also tax supplemental wages; enter your state rate, or zero for a state with no income tax.
A worked example
Take a $10,000 bonus in a state with a 5% supplemental rate and no earlier supplemental pay this year. Federal withholding at 22% is $2,200, FICA at 7.65% is $765, and state tax at 5% is $500. That is $3,465 withheld, leaving $6,535, about 65% of the gross. The donut chart splits the payment into take-home, federal withholding, FICA and state tax.
Assumptions and limitations
This is a planning estimate, not a paycheck. It uses the 2026 IRS flat supplemental rate, the mandatory rate above the one million dollar cap, and the standard 7.65% FICA rate, stored as parameters taken from the IRS and reviewed each year. It assumes the percentage method and that your regular wages for the year are still below the Social Security wage base, so it does not stop the 6.2% component or add the Additional Medicare Tax. It applies one flat state rate and does not model local taxes, the aggregate withholding method, retirement or benefit deductions from the payment, or the final reconciliation on your return. For a precise figure, check current IRS guidance or ask a tax professional.
About This Supplemental Wage Tax Calculator
Use this supplemental wage tax calculator to get an instant, accurate estimate. The figures follow official IRS guidance and every rate and threshold is kept up to date for 2026. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.
Tax year 2026
Frequently asked questions
What are supplemental wages?
How much federal tax is withheld from supplemental wages in 2026?
When does the 37% rate apply?
Is supplemental wage withholding the same as my final tax?
Does this calculator include state tax?
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