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MoneyMath

Bonus Tax Calculator (2026) — Flat 22% vs True Tax

Got a bonus? See exactly how much will be withheld (the scary 22% flat rate) vs what you'll actually owe at tax time. Spoiler: bonuses aren't taxed higher — they're just withheld higher.

🟢 Updated April 2026👤 Reviewed by MoneyMath Editorial⚡ Runs in your browser · inputs never leave your device
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$
Bonus Check Take-Home
$3,268
34.6% withheld. You'll likely get $0 back as a refund.
Federal supplemental withholding (22%)− $1,100
FICA (7.65%)− $383
State withholding− $250
Total withheld$1,733
True federal tax at your bracket$1,100
True total tax owed$1,733
Over-withholding (refund at tax time)$0
Show the formula
withheld federal = bonus × 22% (flat supplemental method)
true federal = bonus × your marginal bracket
refund = withheld − true tax (reconciled at April 15)

The bonus tax myth, debunked

You open your paycheck and your $5,000 bonus has become $2,700. You're furious. "Bonuses are taxed higher!" you tweet. You're wrong — bonuses are withheld higher, not taxed higher. The IRS assumes you might be a high-earner so it withholds at a flat 22% federal supplemental rate, PLUS FICA, PLUS state. At tax time in April, the overpayment comes back as part of your refund. Same total tax. Different timing.

The two bonus withholding methods

  • Flat method (most common): 22% federal flat rate on the entire bonus. Simple and what most payroll systems default to.
  • Aggregate method: Employer adds the bonus to your regular paycheck and withholds based on total. Usually results in even higher withholding for mid-bracket earners because the combined amount pushes you into higher brackets for that check.

Either way, it reconciles at April tax time. If your true bracket is 22% or lower, flat method withholds roughly the right amount. If your true bracket is 24%+, you'll owe some at April. If your true bracket is 12% or lower, you'll get a refund.

The $1,000,000 supplemental cliff

If your YTD supplemental wages exceed $1,000,000 in the calendar year, federal withholding on the excess jumps from 22% to 37%. Executive comp, large signing bonuses, and RSU vests for tech workers at big companies can trigger this. High-income earners should plan accordingly — but note this is still just withholding; your actual marginal rate may be 35% or 37% and it reconciles.

Strategies to reduce bonus tax impact

  • Max your 401(k) with the bonus. Some employers allow pre-tax 401(k) election on bonuses — this avoids the withholding entirely for that portion.
  • HSA and FSA deferrals: Pre-tax dollars reduce both the bonus withholding AND your tax bill.
  • Time the bonus to a low-income year (sabbatical, job change with gap).
  • Donate appreciated stock from prior years to offset bonus income via charitable deduction.

Frequently Asked Questions

Why is my bonus taxed at 40% when my bracket is 22%?

22% federal + 7.65% FICA + 5% state (typical) = 34.65% withholding, but with some mental rounding people report "40%." Combined with any 401(k) or insurance deductions the check looks tiny. The 22% federal is WITHHOLDING, not TAX. You'll reconcile at tax time.

Can I change my bonus withholding rate?

Employers can use either flat 22% OR aggregate method. You cannot directly override. However, you CAN adjust your regular W-4 to under-withhold on subsequent paychecks, effectively offsetting bonus over-withholding.

Do signing bonuses work the same way?

Yes. Sign-on bonuses, annual bonuses, commission, retention bonuses, referral bonuses, and non-discretionary performance bonuses all follow the same supplemental wage rules.

What if my bonus is paid in stock (RSUs)?

RSUs vest and become taxable as supplemental income — same 22% flat withholding (or 37% above $1M YTD). Many tech companies automatically sell-to-cover, which triggers a capital gains event on the sold shares (usually $0 or small loss given same-day sale).

What if I get a bonus in December and don't want to pay tax this year?

Limited options. Bonuses are taxed in the year received (cash basis). Some employers allow deferred-comp elections for executives. 401(k) contributions from the bonus can shift tax to future years.