Bonus Tax Calculator

What is a bonus tax calculator?

A bonus tax calculator estimates your take-home pay from a bonus after selected payroll deductions. Enter your bonus, wages paid so far this year, state withholding rate and 401(k) contribution percent to see an estimate.

The calculator applies the optional federal supplemental-wage withholding rate of 22%. It also estimates Social Security withholding at 6.2% up to the 2026 wage base of $184,500, and Medicare withholding at 1.45%. Your state withholding and 401(k) amounts depend on the rates you enter.

Why bonus withholding matters

A bonus can look much smaller after payroll deductions than its gross amount. Estimating the net amount helps you decide how much to set aside for bills, debt, savings or a planned purchase before the bonus arrives.

Withholding is not the same as your final tax bill. A bonus may have federal tax withheld using a flat rate, but your final federal income tax is determined when you file based on your full tax situation. Your paycheck can also differ if payroll uses a different withholding method or applies deductions not included here.

Use the estimate to plan cash flow, not to decide your final tax liability. For tax questions or decisions about withholding, confirm your situation with a qualified tax professional.

How to use this bonus tax calculator

1. Enter the gross bonus amount before taxes or other deductions.
2. Enter your wages paid so far this year. The calculator uses this figure to estimate how much of the Social Security wage base remains available for the bonus.
3. Enter your state withholding rate. If you do not want to include state withholding, enter 0, as in the sample.
4. Enter the percent of the bonus you expect to put into your 401(k). If no contribution will come from the bonus, enter 0.
5. Review the estimated bonus after taxes and the itemized deductions. Compare the result with the amount you expect to receive from payroll.

Bonus tax calculator example

How to read your bonus tax estimate

The net bonus is the estimated amount left after the deductions shown. The deduction rows help you see which inputs account for the difference between your gross bonus and your estimated take-home amount.

Social Security withholding depends on your wages paid so far because the 6.2% rate applies only up to the 2026 wage base of $184,500. If your wages plus bonus reach that limit, the estimate should reflect that only the remaining wage base is subject to Social Security withholding. Medicare is shown at 1.45%. This calculator does not show every possible payroll deduction or tax adjustment, so check your pay statement for the actual amounts.

How to plan around your bonus

1. 01

   Check the payroll estimate

   Ask payroll how your employer will withhold federal tax on the bonus and whether it will be paid separately or with regular wages. Compare its estimate with this bonus calculator before assigning the money to a purchase or bill.

2. 02

   Choose a 401(k) contribution that fits your plan

   If your plan allows contributions from bonuses, decide whether you want more of the bonus in your paycheck or more directed to retirement savings. Raising the contribution can reduce the cash you receive now; review your plan details and confirm your choice with a qualified tax professional.

3. 03

   Plan for state withholding

   Enter the state withholding rate that applies to your paycheck rather than assuming the federal rate covers it. If you are unsure which rate to use, check your payroll information or ask payroll.

4. 04

   Give the net amount a job

   Base your spending plan on the estimated net bonus, not the gross amount. You might assign it to a specific debt payment, savings goal or planned expense, then revise the plan after your pay statement confirms the actual deposit.

Common bonus tax calculator mistakes

• Treating withholding as the final tax

  The federal amount shown is withholding, not a calculation of your final tax bill. Your full tax situation determines what you owe when you file.

• Leaving out wages already paid

  Wages paid so far affect the Social Security estimate because withholding applies only up to the wage base. Use your current year-to-date wages from a pay statement.

• Entering a whole-number rate instead of a percent

  Enter state withholding and your 401(k) contribution as percentages in the format the calculator requests. Check the result if a deduction looks unexpectedly large or small.

• Assuming the estimate includes every deduction

  The result includes only the items listed: federal withholding, Social Security, Medicare, state withholding and 401(k). Compare it with payroll’s calculation if your check includes other deductions.

The bonus tax formula

Key terms

Supplemental wages

Pay outside regular wages, such as a bonus. The calculator estimates federal withholding using the optional flat rate described in the method.

Withholding

Money your employer deducts from pay and sends toward taxes. It is an estimate paid during the year, not your final tax calculation.

Social Security wage base

The yearly wage limit used for Social Security withholding. The calculator uses the 2026 wage base of $184,500.