Estimated take-home
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Use the gross supplemental payment shown by payroll.
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Choose the payroll treatment you want to model; the result still compares both methods.
A typical 401(k) deferral reduces income-tax wages but usually not FICA wages.
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This determines whether part of the current payment crosses the $1 million mandatory-rate threshold.
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Used by the aggregate-method comparison and ignored by the percentage method.
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Used for the $184,500 Social Security wage base and $200,000 Additional Medicare withholding threshold.
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Use 0% for a federal-only estimate.
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Used only for the comparison row; it does not change payroll withholding.
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Keep $0 unless payroll confirms that part of the deferral also reduces FICA wages.
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Leave off unless the employee's current Form W-4 uses Step 2(c).
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Annual other income amount used by the Pub. 15-T worksheet.
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Annual deductions amount used by the Pub. 15-T worksheet.
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Annual credits reduce tentative annual withholding, not below zero.
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Per-paycheck extra withholding used by the aggregate comparison.
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Keep $0 to calculate regular-pay withholding from the same 2026 schedule.
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Paycheck Calculator Estimate 2026 U.S. take-home pay for hourly or salaried work with federal income tax, FICA and deductions plus user-entered local withholding.
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A bonus can arrive with a much smaller deposit than its headline amount. Payroll may subtract federal income-tax withholding, Social Security and Medicare taxes, state or local withholding, and any elected deferral before the employee receives the remaining cash.

In U.S. payroll, bonuses and commissions are usually treated as supplemental wages. A separately identified payment may use the optional percentage method, while a payment handled with regular wages may use the aggregate method. Those methods decide how much federal income tax is withheld now. They do not decide the employee's final income-tax liability for the year.

Withholding
A prepayment collected through payroll and credited on the tax return.
Income-taxable wages
The bonus amount subject to federal income-tax withholding after a qualifying deferral.
FICA wages
The wage base for Social Security and Medicare. A typical 401(k) deferral reduces federal income-taxable wages but not FICA wages.
Take-home
Gross bonus minus the modeled deferral and payroll withholding.

Two annual thresholds can change the paycheck sharply. For 2026, the employee Social Security rate applies only until wages reach the $184,500 wage base. The 0.9% Additional Medicare withholding begins when wages paid by an employer exceed $200,000. Separately, the part of annual supplemental wages above $1 million uses the mandatory 37% federal withholding rate instead of the 22% supplemental rate.

The aggregate method is more dependent on payroll context. Regular taxable wages, pay frequency, filing status, and Form W-4 entries affect the withholding on a combined paycheck, so two employees receiving the same bonus may see different federal withholding.

A payroll estimate cannot reproduce every employer code or state rule. Final tax liability also depends on total annual income, deductions, credits, filing status, and other payments. Use the estimate for cash planning and compare it with the actual pay stub or a payroll professional when a consequential decision depends on it.

How to Use This Tool:

Model the payroll treatment expected for this payment, then supply the year-to-date values that determine threshold crossings.

  1. Enter the Gross bonus, choose the Federal withholding method, and add any Income-tax pre-tax deferral. The deferral cannot exceed the bonus.
  2. Enter Prior supplemental wages this year, Regular taxable wages this period, the Pay frequency, and Form W-4 filing status. These values determine the $1 million split and the aggregate-method comparison.
  3. Add YTD FICA wages before bonus and a verified State and local withholding rate. Choose whether that rate applies to the gross bonus or the amount after the income-tax deferral.
  4. Review Estimated take-home and the two federal-method totals. If payroll supplied a known regular federal withholding amount or uses additional Form W-4 entries, enter those under Advanced before relying on the aggregate result.

Interpreting Results:

Estimated take-home is the modeled cash from this bonus, not a refund forecast or a final-tax calculation. The retained percentage uses the original gross bonus as its denominator, so a large deferral lowers the displayed cash rate even though the deferral may still belong to the employee in a retirement account.

  • Federal method comparison shows how payroll treatment changes current withholding. It does not imply that the lower method is the employee's true tax rate.
  • A negative federal withholding gap means the chosen federal withholding is below the optional marginal-rate comparison. That comparison is a planning cue only.
  • Check the Social Security taxable amount when year-to-date wages are near $184,500 and the Additional Medicare amount near $200,000.
  • Confirm the actual method, deferral tax treatment, and state rate with payroll when the pay stub needs to match closely.

Technical Details:

The 2026 model separates federal income-tax wages from FICA wages before applying the percentage or aggregate method. Monetary components are rounded to cents at their stated calculation steps, and the selected federal result then joins Social Security, Medicare, Additional Medicare, and the user-supplied state or local amount.

Formula Core

Let B be gross bonus, D the income-tax deferral, E the FICA-exempt portion of that deferral, and S prior supplemental wages. The two taxable bonus bases are:

TI=B−D TF=B−E

The percentage method splits income-taxable bonus wages at the $1 million annual supplemental-wage boundary. Amounts through that boundary use 22%; only the excess uses 37%.

FP=0.22×min(TI,max(0,1000000−S)) +0.37×max(0,TI−max(0,1000000−S))

For the aggregate method, 2026 Publication 15-T annualizes the combined payroll-period wages, applies the selected Form W-4 schedule, returns the result to the pay period, and subtracts regular-pay withholding. A known regular federal amount overrides the computed regular amount when it is greater than zero. Any portion above the $1 million supplemental-wage boundary is then added at 37%.

FA=max(0,W(R+T22)−WR)+0.37×T37

FICA withholding uses the FICA-taxable bonus. Social Security applies only to the unused part of the 2026 wage base; Medicare applies to all FICA wages, and Additional Medicare applies to the part that crosses the employer withholding threshold.

SS=0.062×min(TF,max(0,184500−Y)) Medicare=0.0145×TF+0.009×crossing(Y,TF,200000) Net=B−D−Federal−SS−Medicare−StateLocal
Rule2026 valueBoundary
Optional supplemental rate22%Applies to the eligible portion at or below $1 million of annual supplemental wages.
Mandatory supplemental rate37%Applies only to the portion above $1 million.
Employee Social Security6.2%Applies through $184,500 of 2026 Social Security wages.
Employee Medicare1.45%No wage-base ceiling.
Additional Medicare withholding0.9%Begins on employer-paid wages above $200,000, without regard to filing status.

Accuracy and Limitations:

This is an educational payroll estimate for 2026 U.S. rules, not tax advice or a substitute for an employer's payroll system.

  • The state and local rate is supplied by the reader; no jurisdiction lookup or local supplemental-wage rule is applied.
  • The 0.9% Additional Medicare amount models employer withholding at $200,000. The employee's final Additional Medicare liability can use a different filing-status threshold.
  • A deferral reduces FICA wages only when the FICA-exempt part of deferral is entered. Keep it at zero for a typical 401(k) election unless payroll confirms otherwise.
  • Actual pay stubs may include benefits, garnishments, employer-specific rounding, imputed income, or other deductions outside this model.

Worked Examples:

Crossing two annual thresholds

A $10,000 bonus after $995,000 of prior supplemental wages splits into $5,000 at 22% and $5,000 at 37%, producing $2,950 of federal percentage-method withholding. If prior FICA wages are $199,500, Social Security is already above its 2026 wage base, ordinary Medicare is $145, and $9,500 crosses the employer's Additional Medicare threshold for another $85.50. With no state withholding or deferral, estimated take-home is $6,819.50.

References: