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Bonus Take-Home Calculator

Enter your gross bonus to see exactly how much goes to Social Security and Medicare — plus an estimate of the federal income tax your employer will withhold using the IRS supplemental flat rate.

Informational only — not financial advice. FICA figures are exact per IRS Publication 15. Income tax withholding is an estimate only; does not include state income tax.

Your Bonus

Shows FICA (Social Security & Medicare) deducted from your bonus as a supplemental wage payment. An income tax withholding estimate is shown separately using the 2026 IRS flat supplemental rate — your employer may use this rate or the aggregate method.

Enter your bonus amount to see the FICA breakdown and estimated take-home.

How this calculator works

What is a supplemental wage payment?

The IRS treats bonuses, commissions, and other one-time payments as “supplemental wages” — separate from regular salary payments. The key difference is how income tax is withheld (see below). FICA deductions work the same way as on any other paycheck.

Step 1 — FICA on the full bonus amount

FICA applies to the full gross bonus with no exemptions. Both Social Security and Medicare are owed on supplemental wages just as they are on regular wages:

  • Social Security: 6.2% on wages up to the 2026 annual wage base of $184,500 (SSA.gov). If your YTD wages already reach the cap before the bonus, Social Security is $0 on the bonus.
  • Medicare: 1.45% on all FICA-taxable wages — no ceiling (IRS Publication 15).
  • Additional Medicare Tax: an extra 0.9% applies once your combined FICA-taxable wages for the year exceed $200,000. Entering your YTD wages lets the calculator apply this correctly.

Step 2 — Income tax withholding (informational estimate)

Your employer is also required to withhold federal income tax on bonus payments. There are two IRS-approved methods:

  • Flat supplemental rate: 22% for bonuses up to $1,000,000 (37% on the excess above $1,000,000). This is the most common method for standalone bonus payments. Source: IRS Publication 15-T (2026).
  • Aggregate method: combines the bonus with your most recent regular paycheck and calculates withholding on the total using your W-4. This often results in more withholding, especially for high earners.

The calculator shows the flat-rate estimate as a reference — it is labeled “Estimate Only” because your employer’s choice of method and your W-4 elections will determine the actual amount withheld. The net you see after FICA is a guaranteed calculation; the income tax estimate is informational context.

What this calculator doesn’t cover

State income tax. Most states also withhold income tax on bonuses. State supplemental rates and methods vary widely and are not included.

Pre-tax benefit deductions. Section 125 deductions (health, dental, FSA) and 401(k) contributions are not factored in. Use the Paycheck Take-Home Calculator to model those.

Employer FICA match. Your employer pays an equal share of Social Security and Medicare on your bonus — that cost does not appear here because it does not affect your take-home pay.

Sources: IRS Publication 15 (Circular E) · IRS Publication 15-T (Supplemental Withholding Rate) · SSA Contribution and Benefit Base

Last reviewed: June 2026

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