2026 Calculator
Bonus Tax Calculator 2026 - Flat 22% vs Aggregate Method
Calculate how much tax will be withheld from your 2026 bonus. Compare the flat 22% supplemental rate vs. aggregate method, including FICA (Social Security + Medicare). Instant results with worked examples.
Bonus Tax Calculator 2026: Flat 22% vs Aggregate Method
When you receive a bonus, your employer must withhold federal income tax and FICA before paying you. The IRS provides two methods for calculating federal withholding on supplemental wages like bonuses, commissions, and severance pay. The most common is the flat 22% method (or 37% on amounts exceeding $1,000,000). The alternative aggregate method combines your bonus with regular wages and computes withholding on the total. Use this calculator to estimate your take-home pay under either method, including Social Security (6.2%) and Medicare (1.45%) taxes.
How Bonus Tax Withholding Works
Flat Percentage Method (22%)
Under IRS Publication 15, employers can withhold a flat 22% on supplemental wages up to $1,000,000 per year. This is the simplest and most widely used method. It applies regardless of your regular income or filing status. If your total supplemental wages for the year exceed $1,000,000, the excess must be withheld at 37% (the top marginal rate for 2026).
Aggregate Method
The aggregate method treats your bonus as part of your regular pay for the pay period. Your employer adds the bonus to your most recent paycheck, calculates the total withholding as if it were a single regular payment, then subtracts the tax already withheld on your regular wages. The remainder is withheld from the bonus. This method can result in higher or lower withholding than the flat method, depending on your income level and bracket.
FICA on Bonuses
Regardless of the withholding method, bonuses are subject to FICA taxes: Social Security at 6.2% (up to the $184,500 wage base) and Medicare at 1.45% (no cap). If your combined wages and bonus exceed $200,000, an additional 0.9% Medicare surtax applies to the excess.
Worked Examples
Example 1: $5,000 Bonus, Flat Method
Profile: $5,000 bonus, flat 22% method, single filer
Social Security (6.2%) = $310.00
Medicare (1.45%) = $72.50
Total withholding = $1,482.50
Net bonus = $3,517.50
Example 2: $10,000 Bonus, Aggregate Method
Profile: $10,000 bonus, aggregate method, single filer, $60,000 regular annual wages, $7,872.00 withheld YTD
Federal withholding = $0.00
Social Security (6.2%) = $620.00
Medicare (1.45%) = $145.00
Total withholding = $765.00
Net bonus = $9,235.00
Example 3: $25,000 Bonus, Flat Method
Profile: $25,000 bonus, flat 22% method, single filer
Social Security (6.2%) = $1,550.00
Medicare (1.45%) = $362.50
Total withholding = $7,412.50
Net bonus = $17,587.50