to estimate withholding and take-home
Supplemental Wages · IRS Pub 15 §7 · 22% Flat / 37% Over $1M · TY 2026
Estimate federal withholding on your bonus under IRS supplemental wage rules. Compares the flat 22 percent rate to the aggregate method, then adds Social Security, Medicare, and Additional Medicare Tax. Your take-home bonus is what remains after all four withholding layers.
Want the full rules, examples, edge cases, and planning context behind this calculation? Read the companion guide.
Read the Bonus Tax Guide →For 2026, the IRS supplemental withholding rate on bonuses is 22 percent up to $1 million per calendar year and 37 percent on the excess. On top of that, Social Security (6.2 percent up to $184,500 in wages) and Medicare (1.45 percent, plus 0.9 percent over $200K single or $250K MFJ) apply to the bonus. A $10,000 bonus for a mid-income MFJ employee typically loses about $3,000 to federal withholding and FICA combined. That is withholding, not final tax - your actual rate is set at filing.
| Item | Value | Status |
|---|---|---|
| Supplemental flat withholding rate (bonus ≤ $1M) | 22% | Confirmed |
| Supplemental rate on amount over $1M (per employer, calendar year) | 37% | Confirmed |
| Social Security rate (employee share) | 6.2% | Confirmed |
| 2026 Social Security wage base | $184,500 | Confirmed |
| Medicare rate (employee share) | 1.45% | Confirmed |
| Additional Medicare Tax rate | 0.9% | Confirmed |
| Additional Medicare threshold: Single / HOH | $200,000 | Confirmed |
| Additional Medicare threshold: MFJ | $250,000 | Confirmed |
| Additional Medicare threshold: MFS | $125,000 | Confirmed |
| Employer mandatory Additional Medicare withholding threshold | $200,000 (per employee, regardless of filing status) | Confirmed |
| Governing statute (supplemental wages) | IRC §3402(g); IRS Pub 15 §7 | Confirmed |
| Aggregate method tables | IRS Pub 15-T Percentage Method | Confirmed |
| OBBBA rate extension | PL 119-21 permanently extended TCJA rates, keeping 22% / 37% | Confirmed |
| State supplemental rates | Varies by state - see state DOR | Provisional |
This calculator applies IRS supplemental wage rules under IRC §3402(g) and Publication 15 section 7 for tax year 2026. The calculation proceeds in four sequential steps. For the full statutory background and employer election mechanics, see our Bonus Tax Withholding Guide.
The employer withholds a flat 22 percent on bonuses identified separately from regular wages, up to $1 million of cumulative supplemental wages from that employer during the calendar year. On any amount above $1 million, the rate jumps to 37 percent. This is a withholding rule, not a tax rule.
If (YTD supplemental + current bonus) ≤ $1,000,000: Federal withholding = Bonus × 22%
If (YTD supplemental + current bonus) > $1,000,000: Federal withholding = 22% on the portion up to $1M + 37% on the excess
Under the aggregate method, the employer combines the bonus with your regular paycheck, calculates federal income tax withholding on the combined amount using Publication 15-T percentage method tables (based on your Form W-4), and subtracts the withholding that would have applied to your regular pay alone. The difference is the withholding attributable to the bonus.
Aggregate method steps: (1) Annualize regular pay + bonus = (regular pay × pay periods) + bonus; (2) Apply 2026 Pub 15-T percentage method table after standard deduction; (3) Annualize regular pay alone = regular pay × pay periods; (4) Apply the same table to regular alone; (5) Bonus withholding = tax on combined − tax on regular alone. This calculator uses a simplified annualization on the 2026 bracket structure (Rev. Proc. 2025-32); actual Pub 15-T tables include per-period bracket breakpoints that may produce slightly different results.
Social Security tax (6.2 percent) applies to bonuses up to the 2026 annual wage base of $184,500. Once your combined YTD wages plus bonus exceed $184,500, no further Social Security tax is withheld. Medicare tax (1.45 percent) applies to the entire bonus with no wage cap.
Social Security withholding = MIN(Bonus, MAX(0, $184,500 − YTD Wages)) × 6.2%
Medicare withholding = Bonus × 1.45%
Under IRC §3101(b)(2), an additional 0.9 percent Medicare tax applies to wages (plus self-employment income) above $200,000 for single and head of household filers, $250,000 married filing jointly, and $125,000 married filing separately. Employers are required to begin withholding the 0.9 percent once an employee's calendar-year wages from that employer exceed $200,000, regardless of the employee's filing status. Final liability is reconciled on Form 8959 with the individual return.
Additional Medicare withholding = MAX(0, (YTD Wages + Bonus) − Filing Threshold) × 0.9%
The aggregate method tends to produce higher withholding for high-income employees (whose marginal brackets exceed 22 percent) and lower withholding for low-income employees (whose marginal brackets are below 22 percent). Employers usually default to flat rate because it is administratively simpler.
In Example 2, a mid-income MFJ couple sees a 23.5 percent haircut on the bonus even though the Social Security wage base is already reached. In Example 3, the high-income single filer is structurally under-withheld under the flat method and should plan to cover the shortfall at filing, or adjust their W-4 to add extra withholding on regular paychecks.
At LMN Tax Inc, clients routinely call us in December asking why a year-end bonus "disappeared." The usual answer is that the 22 percent flat federal rate plus 7.65 percent FICA plus state tax can total 35 percent or more before the deposit lands. The money is not lost - it is withheld. For high earners, we also see the opposite problem: a $50,000 bonus at 32 percent marginal rate but only 22 percent withheld leaves a $5,000 underpayment that surfaces in April. The practical fix is either a Q4 estimated payment or a one-time W-4 extra-withholding bump on the next regular paycheck. For employees with a 401(k) that accepts bonus deferrals, electing to defer part of the bonus pre-tax is often the highest-leverage move available in the last week of the year.
If the 22 percent flat rate is below your marginal tax bracket (typically 24 percent and above), you may owe at filing. Make an estimated tax payment through IRS Direct Pay by the next quarterly deadline or update your Form W-4 to add extra withholding on regular paychecks. If you want to see exactly how much additional withholding covers the gap, run the W-4 Withholding Calculator with your projected annual wages including the bonus.
If you received a bonus that affects your anticipated refund, use the Refund Date Estimator to project your IRS deposit date once you file. For context on what drives the IRS 21-day processing window, see the IRS Refund Timeline Guide.
For the full statutory background on supplemental wages, the flat-rate-vs-aggregate election, and year-end planning moves (401(k) deferral, HSA contribution, estimated payment), read our Bonus Tax Withholding Guide.
If your bonus comes in the form of tip income or overtime premium, you may qualify for the new OBBBA deductions on your tax return (up to $25,000 for qualified tips and up to $12,500 / $25,000 for qualified overtime). Use the No Tax on Tips Calculator or No Tax on Overtime Calculator for the deduction math. Those deductions do not change the employer's withholding; they apply at filing.