Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Bonus after withholding
$9,803
You keep
65.3%
Federal supplemental withholding
$3,300
FICA
$1,148
State tax
$750
Likely refunded at filing
$0
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter bonus amount ($).
- 2Enter state tax rate (%).
- 3Enter your actual marginal rate (%).
- 4Read your bonus after withholding on the right — it updates as you type.
- 5Hit Share to keep the scenario or send it to someone.
About this calculator
Employers usually withhold bonuses at a flat 22% supplemental federal rate (37% above $1 million), plus FICA and state tax. That is withholding, not your final tax bill — if your real rate is lower you get it back at filing.
Worked example
Using the values the calculator loads with:
Inputs
- Bonus amount: 15000 $
- State tax rate: 5 %
- Your actual marginal rate: 24 %
Results
- Bonus after withholding: $9,802.50
- You keep: 65.3%
- Federal supplemental withholding: $3,300.00
- FICA: $1,147.50
- State tax: $750.00
- Likely refunded at filing: $0.00
What each field means
Inputs
- Bonus amount ($)
- The bonus amount used in the calculation, measured in $. Starts at 15000 $ so you have a working example on load.
- State tax rate (%)
- The state tax rate used in the calculation, measured in %. Starts at 5 % so you have a working example on load. Accepted range: 0–15 %.
- Your actual marginal rate (%)
- The your actual marginal rate used in the calculation, measured in %. Starts at 24 % so you have a working example on load. Accepted range: 0–50 %.
Results
- Bonus after withholding
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- You keep
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Federal supplemental withholding
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- FICA
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- State tax
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Likely refunded at filing
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the bonus tax calculator work?
Employers usually withhold bonuses at a flat 22% supplemental federal rate (37% above $1 million), plus FICA and state tax. That is withholding, not your final tax bill — if your real rate is lower you get it back at filing. The underlying maths is: Net bonus = Bonus − (22% or 37% supplemental federal) − FICA 7.65% − state rate.
What do I need to enter?
3 values: bonus amount, state tax rate, and your actual marginal rate. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the bonus after withholding result mean?
It is returned as a money amount in US dollars and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Bonus Tax Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/bonus-tax
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/bonus-tax" target="_blank" rel="noopener">Bonus Tax Calculator — RevenueLab</a> (2026).</p>
Source: [Bonus Tax Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/bonus-tax) (2026).