Why is my bonus taxed at 22%?

The short answer

22% is a withholding rate, not a tax rate. Your employer is allowed to hold back a flat 22% of a bonus instead of running it through your W-4, and the difference between what that flat rate takes and what the bonus actually costs gets settled when you file.

Which direction the difference goes depends on your bracket. A single filer earning $60,000 gets money back. The same filer earning $150,000 owes a little more. Both cases are worked through below on 2026 tables.

Where the 22% comes from

The IRS calls a bonus a supplemental wage, the same category as commissions, severance, back pay, and prizes. Publication 15, the employer's withholding guide, gives payroll two ways to handle one.

The percentage method is the flat one: withhold 22% of the bonus for federal income tax and stop there. That rate covers the first $1,000,000 of supplemental wages an employee receives in a calendar year. Past that point the rate on the excess is 37% and the employer has no choice about it.

The aggregate method is the other one: add the bonus to a regular paycheck, work out withholding on the combined amount as though it were ordinary pay for that period, subtract what was already withheld on the regular wages, and hold back the rest. This one follows your W-4, so a filer in a low bracket usually sees less taken and a filer in a high bracket usually sees more.

Which method you got is a payroll decision, not yours. The tell is arithmetic: if the federal line on the bonus is exactly 22% of the gross bonus, it was the flat rate.

Neither method is a tax rate. A bonus is ordinary wage income. At filing it stacks on top of everything else you earned and is taxed in whatever brackets that total lands in. Withholding is only a prepayment against the year's bill.

Worked example: a bonus in the 12% bracket

A single filer earning $60,000 in a state with no income tax receives a $5,000 bonus, withheld at the flat rate. Here is the check.

What payroll holds back on the $5,000 bonus

$60,000 salary, single filer, percentage method

Federal, 22% of the bonus: $1,100.00
Social Security, 6.2%: $310.00
Medicare, 1.45%: $72.50
Total withheld: $1,482.50
Bonus check: $3,517.50

What the bonus actually costs at filing

Tax on salary plus bonus, minus tax on salary alone

Federal income tax the bonus adds: $600.00
State income tax the bonus adds: $0.00
Social Security and Medicare: $382.50
Actual cost of the bonus: $982.50
Over-withheld, returned as refund: $500.00

The salary and the bonus together still sit inside the 12% federal bracket, so the bonus is taxed at 12%, not 22%. The flat rate held back $500.00 more than the year owes on it, and that comes back in the refund. Nothing was lost, but the money sat with the Treasury until the return was filed.

Worked example: the same bonus, higher up

Same $5,000 bonus, same flat withholding, same state. The only change is the salary underneath it: $150,000 instead of $60,000.

$150,000 salary, $5,000 bonus

Single filer, no state income tax

Total withheld from the check: $1,482.50
Federal income tax the bonus adds: $1,200.00
Social Security and Medicare: $382.50
Actual cost of the bonus: $1,582.50
Under-withheld, owed at filing: $100.00

Here the combined income sits in the 24% bracket, above the flat withholding rate, so the check held back less than the bonus costs. The shortfall is small on its own, but it is the reason a bonus can leave someone with a smaller refund than they expected in a year they got one.

Add a state to the same example and the shortfall grows. In California, the same $5,000 bonus on a $150,000 salary adds $465.00 of state income tax, on top of the federal and FICA lines, for a total cost of $2,047.50. The flat federal method withholds nothing toward that.

The part that never comes back

Social Security and Medicare come out of a bonus exactly as they come out of regular pay: 6.2% on wages up to the year's Social Security wage base, $184,500 in 2026, plus 1.45% Medicare on all of it with no ceiling, plus another 0.9% on wages past the Additional Medicare threshold.

Unlike income tax, none of that is reconciled on the return. There is no year-end true-up that gives FICA back, which is why the FICA line is identical in both columns of the examples above. It is the one part of a bonus's cost that is settled the moment the check is cut.

One exception cuts the other way. If your salary has already reached the Social Security wage base before the bonus is paid, the 6.2% does not apply to it, and a bonus that straddles the base pays only on the part below it. That is worked out in the guide on when Social Security withholding stops.

State tax is usually missing from the check

The flat 22% is a federal rule. States handle supplemental wages their own way: some publish a flat supplemental rate of their own, some tell employers to use the regular withholding tables, and there are 9 states that do not tax wage income at all. That variation is why a bonus in one state can leave a refund and the identical bonus in another can leave a balance due.

The companion guide, what a bonus keeps in 12 states, runs the same bonus through twelve state tax systems and says plainly which column is a withholding figure and which is an estimate.

What this does not cover

Your W-4. If your employer used the aggregate method, allowances, extra withholding, and a second job all move the federal line on the check. The figures here model the flat rate only.
Other supplemental wages. The $1,000,000 test counts every supplemental payment an employee receives in the year, not one bonus at a time. These examples assume this is the only one.
Deferrals. Sending part of a bonus to a traditional 401(k) lowers the income-tax side but not FICA, since deferrals are still Social Security and Medicare wages. A payroll HSA contribution lowers both.
State withholding on the check itself. The actual-cost figures are the state income tax the bonus adds for the year, which is not the same thing as what a state tells an employer to withhold on the day.
Everything else on a return. Other income, credits, itemized deductions, and dependents all move the real number. These are planning estimates on 2026 tables, not tax advice and not your exact withholding.