Overtime, bonuses and how they are taxed in the United States
Reviewed by Mellow Editorial Team, HR & payroll content team
Overtime pay and bonuses are taxed as ordinary income in the United States — meaning they are subject to federal income tax, FICA, and any applicable state income tax, just like regular wages. The key difference is in how employers calculate and withhold those taxes.
How overtime pay is taxed
The Fair Labor Standards Act requires most employers to pay non-exempt employees at least 1.5 times their regular rate for hours worked beyond 40 in a workweek. From a tax perspective, that overtime pay is simply part of the employee's total wages for the pay period.
When you run payroll, you add overtime earnings to regular wages and withhold federal income tax on the combined total. Because federal income tax uses progressive brackets ranging from 10% to 37%, an employee who earns significantly more in a given pay period due to overtime may have more tax withheld that period — but their overall annual liability is determined by their total income for the year, not by any single paycheck.
FICA applies to overtime pay in the same way it applies to regular wages:
- Social Security tax: 6.2% on the employee's wages up to the annual wage base, matched by the employer at 6.2%.
- Medicare tax: 1.45% on all wages with no cap, matched by the employer.
- Additional Medicare Tax: 0.9% on high-earning employees above the relevant threshold — this is an employee-only obligation; there is no employer match.
State income tax also applies where the state levies it. Employers in states like Texas, Florida, and Washington pay no state income tax on wages; employers in most other states do.
How bonuses are taxed
The IRS treats bonuses as "supplemental wages" — compensation paid in addition to an employee's regular wages. This classification matters because it gives employers two options for federal income tax withholding.
Flat rate method: Withhold a flat federal rate on the bonus amount. This is the simpler approach and is often used when a bonus is paid separately from a regular paycheck. Check current IRS guidance for the applicable flat supplemental rate, as it is set by the IRS and can change.
Aggregate method: Add the bonus to the employee's most recent regular wages, calculate withholding on the combined total based on their Form W-4 elections, then subtract what was already withheld on the regular wages. The remainder is withheld from the bonus. This tends to reflect actual annual liability more closely but requires more calculation.
Either way, FICA applies to bonuses exactly as it does to other wages — Social Security at 6.2% up to the wage base, Medicare at 1.45% with no cap, and the Additional Medicare surcharge for high earners. Employers match the Social Security and Medicare portions.
One practical point: if an employee has already hit the Social Security wage base earlier in the year, no additional Social Security tax is withheld or matched on a bonus paid after that point. Medicare, however, continues with no cap.
The W-4 and its effect on withholding
Withholding calculations for both overtime and bonuses depend heavily on what the employee has submitted on Form W-4. Employees who expect significant overtime or large bonuses during the year can adjust their W-4 to request additional withholding per pay period, reducing the chance of a tax bill when they file.
As an employer, you are responsible for withholding based on the current W-4 on file. You are not responsible for correcting under-withholding caused by an employee's own W-4 elections, but it is good practice to remind employees annually that they can update their form.
Reporting and depositing
Whatever method you use, the taxes withheld from overtime and bonuses must be deposited on your regular FICA and federal income tax deposit schedule — either monthly or semi-weekly, depending on your lookback period. Errors in timing attract penalties.
At year end, overtime pay and bonuses are included in Box 1 (wages, tips, other compensation) of the employee's Form W-2. W-2s must be furnished to employees and filed with the Social Security Administration by January 31. Quarterly, these wages and the associated taxes appear on Form 941. If you need a broader view of how payroll runs across different employment setups, the mechanics of supplemental wages are a useful place to start.
Common mistakes to avoid
- Using the flat rate method when the aggregate method is required. The flat rate method is only available when bonus payments are clearly separate from regular wages. If you combine them on the same check, you must use the aggregate method.
- Forgetting FICA on bonuses. Some employers mistakenly treat bonuses as outside the scope of payroll taxes. They are not.
- Missing the wage base cutoff. Track each employee's cumulative earnings carefully so you stop withholding and matching Social Security once the annual wage base is reached — overpaying is a hassle to correct.
- Ignoring state rules. Several states have their own supplemental wage withholding rates or rules that differ from federal treatment. Confirm your state's requirements with your payroll system or a tax advisor.
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