Washington Bonus Calculator
Bonus Details
Federal W-4 Settings
Washington Employee Programs
Deductions (Per Regular Paycheck)
Year-To-Date Data (Optional, Improves Accuracy)
Your Bonus Estimate
- Bonuses are not taxed at a special bonus rate when you file. They are ordinary income taxed at your regular federal marginal rate.
- The 22 percent federal flat rate is simply a withholding method employers use on supplemental wages paid separately. It is not a final tax rate.
- Washington has no state income tax on wages, so there is no Washington bonus income tax withholding and no Washington supplemental wage income tax rate.
- Washington employees may still have state payroll premiums withheld. This calculator includes Washington Paid Leave and WA Cares when selected.
- The federal aggregate method combines your bonus with regular wages and applies your W-4 settings. The bonus portion equals the difference between combined withholding and regular-only withholding.
- When you file your return, your total annual income determines your true federal liability. Over-withholding becomes part of your refund. Under-withholding becomes tax due.
- Gross-up mode solves for the gross bonus your employer must pay so your take-home equals the target you enter.
What Is the Washington Bonus Calculator?
The Washington Bonus Calculator is a payroll withholding estimator for bonuses paid to Washington employees. It calculates bonus take-home pay, the effective withholding rate, individual payroll taxes and premiums, full-pay-period results, and an annual federal tax snapshot. You can use either the federal supplemental flat-rate method or the aggregate withholding method.
A Washington bonus calculator estimates your net bonus by subtracting federal income tax withholding, Social Security, Medicare, Additional Medicare Tax when applicable, Washington Paid Leave premiums, and WA Cares premiums. Washington wage income tax is set to zero because the calculator applies no Washington state income tax to wages.
The tool also includes a gross-up mode. Instead of entering a gross bonus, you enter the take-home amount you want. The calculator then solves for the gross bonus required to reach that target under the selected withholding settings.
How the Washington Bonus Calculator Formula Works
The calculator starts with the gross bonus and determines each withholding component separately. The core bonus take-home calculation is:
Here, Bnet is the bonus take-home amount, Bgross is the gross bonus, F is federal income tax withholding, SS is Social Security, M is Medicare, AM is Additional Medicare, PFML is the Washington Paid Leave employee premium, and WC is the WA Cares premium.
Under the flat federal method, the calculator withholds 22% on supplemental wages while cumulative supplemental wages remain within the $1,000,000 threshold. Any portion above that threshold is withheld at 37%.
Under the aggregate method, the calculator adds the bonus to the current regular paycheck, calculates federal withholding on the combined amount, and subtracts the withholding calculated on regular wages alone. Federal withholding uses the selected filing status, pay frequency, and W-4 settings.
Social Security is calculated at 6.2% up to the calculator's 2025 wage base of $176,100. Regular wages use the remaining wage base first, followed by the bonus. Medicare is 1.45% without a wage cap. The calculator applies an additional 0.9% Medicare withholding after year-to-date Medicare wages plus current wages exceed $200,000.
Washington Paid Leave uses an employee rate of 0.657984%, calculated from the coded 0.92% total premium multiplied by a 71.52% employee share. It applies up to $176,100 of wages when enabled. WA Cares uses 0.58% of gross wages with no wage cap in this calculator.
Worked Example
Assume a $5,000 gross bonus, a $75,000 annual salary, biweekly pay, married filing jointly, the flat federal method, no W-4 adjustments, no deductions, no prior year-to-date wages, and both Washington employee premiums enabled.
- Federal bonus withholding: $5,000 × 22% = $1,100.00.
- Social Security: $5,000 × 6.2% = $310.00.
- Medicare: $5,000 × 1.45% = $72.50.
- Additional Medicare: $0.00 because the coded $200,000 withholding threshold is not reached.
- Washington Paid Leave: $5,000 × 0.657984% = $32.8992.
- WA Cares: $5,000 × 0.58% = $29.00.
Total bonus withholding is $1,544.3992. The calculator displays that as $1,544.40. The estimated bonus take-home is $3,455.60, with an effective withholding rate of 30.89%. Under the same inputs, the calculator shows $900.19 as the federal withholding amount under the alternative aggregate method.
Gross-up mode works in reverse. The calculator repeatedly tests possible gross bonuses until it finds an amount whose calculated net bonus reaches the target. The final required gross bonus is rounded upward to the next cent.
How to Use the Washington Bonus Calculator: Step by Step
- Choose Estimate take-home from a bonus amount to start with a gross bonus, or choose Gross-up to start with a desired net bonus.
- Enter your bonus amount or desired take-home target. The amount must be greater than zero.
- Select the federal bonus withholding method. Choose the 22% flat method or the aggregate method that combines the bonus with regular wages.
- Enter your base annual salary and choose your pay frequency: weekly, biweekly, semimonthly, or monthly.
- Select your federal filing status: single, married filing jointly, or head of household.
- Enter any applicable W-4 settings, including Step 2, dependent credits, other annual income, annual deductions, and extra federal withholding per check.
- Choose whether to apply the Washington Paid Leave employee premium and WA Cares premium.
- Enter any pre-tax and post-tax deductions that apply to a regular paycheck. The calculator limits each entered deduction to the regular gross pay amount when performing the calculation.
- Add year-to-date Social Security wages, Medicare wages, supplemental wages, pay periods received, federal withholding, and Washington Paid Leave wages when available.
- Check the acknowledgment confirming that the calculation estimates withholding rather than final tax liability, then calculate the result.
The results show your bonus take-home, effective bonus withholding rate, detailed bonus deductions, full current-pay-period figures, and an annual federal tax snapshot. In gross-up mode, the results also show the required gross bonus. Dollar amounts are displayed as U.S. currency, while percentage results are displayed to two decimal places.
Factors That Can Affect Your Washington Bonus Take-Home
Federal Withholding Method
The selected federal method can materially change the amount withheld from the bonus. The flat method normally applies the coded 22% supplemental rate below the $1,000,000 cumulative supplemental-wage threshold. The aggregate method instead annualizes the combined paycheck using the calculator's federal tax brackets and W-4 settings.
Year-to-Date Wages
Year-to-date information improves calculations that depend on wage limits or thresholds. Prior Social Security wages determine how much of the $176,100 wage base remains. Prior Washington Paid Leave wages serve the same purpose for its $176,100 cap. Prior Medicare wages affect Additional Medicare withholding, while prior supplemental wages affect the federal $1,000,000 supplemental threshold.
W-4 Settings and Regular Pay
For federal paycheck withholding, the calculator annualizes taxable pay and applies the 2025 standard deduction and tax brackets coded for the selected filing status. W-4 Step 2 adds $5,000 to annualized taxable wages. Step 3 reduces calculated annual federal tax, Step 4(a) adds income, Step 4(b) subtracts deductions, and Step 4(c) adds withholding per paycheck.
| Item | How the Calculator Treats It |
|---|---|
| Pre-tax deductions | Reduce regular federal income tax wages, but do not reduce Social Security, Medicare, Washington Paid Leave, or WA Cares wages. |
| Post-tax deductions | Reduce take-home pay only and do not reduce calculated payroll taxes. |
| Washington wage income tax | Set to $0 in bonus and annual results. |
| Washington Paid Leave | Optional employee premium, capped at the coded $176,100 wage base. |
| WA Cares | Optional 0.58% premium with no wage cap in the calculator. |
The annual snapshot is still an estimate. It projects federal withholding using the entered year-to-date federal withholding, remaining regular pay periods, and the selected bonus method. Actual tax liability can differ because the calculator cannot know every part of your tax return, payroll history, employer process, deductions, credits, or other income.
Frequently Asked Questions
How much tax is withheld from a bonus in Washington?
The amount depends on your selected federal withholding method and payroll circumstances. This calculator can apply 22% federal supplemental withholding below the coded $1,000,000 threshold, plus Social Security, Medicare, possible Additional Medicare, Washington Paid Leave, and WA Cares. It calculates Washington income tax on wages as $0.
Does Washington tax bonuses?
This calculator applies no Washington state income tax to bonus wages. Its Washington income tax result is always $0. However, a bonus can still be subject to Washington Paid Leave and WA Cares employee premiums when those options are enabled, in addition to federal income tax and federal payroll taxes.
Is the 22% bonus rate my final federal tax rate?
No. In this calculator, 22% is a federal withholding method for supplemental wages, not the final tax rate on your bonus. The annual federal tax estimate treats the bonus as part of annual income and applies the calculator's progressive federal tax brackets after its deductions and W-4 adjustments.
What is the difference between the flat and aggregate bonus methods?
The flat method applies the coded supplemental withholding rates directly to the bonus. The aggregate method combines the bonus with regular taxable wages for the pay period, calculates federal withholding on the combined amount, then subtracts regular-only withholding. The calculator also displays what federal withholding would be under the other method.
How does the Washington bonus gross-up calculator work?
Gross-up mode starts with the net bonus you want to receive. The calculator repeatedly tests gross bonus amounts and runs the same tax and premium calculations until the estimated net amount meets the target. It then rounds the required gross bonus upward to the nearest cent for display.
Why should I enter year-to-date payroll information?
Year-to-date data helps the calculator apply wage caps and thresholds more realistically. It uses prior wages for Social Security, Medicare, supplemental federal wages, and Washington Paid Leave. It also uses prior federal withholding and the number of pay periods already received when projecting annual federal withholding and a possible refund or amount due.
How accurate is the Washington Bonus Calculator?
The calculator is an estimate based on the 2025 federal and Washington payroll rules coded into the tool and the information you enter. Actual payroll withholding and final tax liability can differ because of employer payroll methods, other income, tax credits, deductions, filing details, updated rules, and information not included in the calculator.