How Much Will My Bonus Be Taxed? The Honest Answer

You got a bonus, the check landed, and a huge chunk was gone before you saw a dollar of it. The most important thing to understand is this: the amount withheld from your bonus is not the amount of tax you actually owe. Almost every article online blurs these two things together. They are completely different, and the gap between them is exactly why your check looked so small, and often why you get money back later.

Withholding vs. tax: the distinction that explains everything

There are two separate events. First, withholding: money your employer pulls out of the bonus check the moment it's paid, and sends to the government on your behalf. Second, your actual tax: the real amount you owe on that income, which isn't settled until you file your return and reconcile everything against your total annual income and tax bracket.

Bonuses are "supplemental wages," and the IRS gives employers a shortcut for withholding on them. The most common method is the flat supplemental rate of 22% federal. Your employer doesn't know your full financial picture, so it applies this flat rate regardless of whether your real marginal rate is higher or lower. That 22% is a withholding estimate, not your tax bill.

What actually comes out of the check

On top of the 22% federal withholding, two more deductions hit almost every bonus:

• FICA (Social Security + Medicare): 7.65%. This is 6.2% Social Security plus 1.45% Medicare. Unlike federal income tax, this is a true tax, not just withholding. Social Security stops once your annual wages pass the yearly wage base limit set by the Social Security Administration, and high earners pay an extra Medicare surtax above an income threshold.
• State (and sometimes local) tax, which varies widely. A few states have no income tax; others apply their own supplemental withholding rate.

So a typical bonus loses roughly 22% + 7.65% = 29.65% federally before any state tax. That's the source of the "they took almost a third!" reaction. To see this modeled against your specific paycheck setup, run the numbers through the paycheck calculator and enter the bonus as additional income.

Worked example 1: a 12%-bracket worker (over-withheld, gets it back)

Imagine you earn a modest salary that puts your marginal rate at 12%, and you receive a $5,000 bonus.

• Federal withholding at 22%: $5,000 x 0.22 = $1,100
• FICA at 7.65%: $5,000 x 0.0765 = $382.50
• Cash you actually see: $5,000 - $1,100 - $382.50 = $3,517.50

But your real federal income tax on that $5,000, at a 12% marginal rate, is only $5,000 x 0.12 = $600. You had $1,100 withheld but owed $600. That $500 over-withholding doesn't vanish, it gets reconciled when you file, and you receive it back as part of your refund. (FICA is a flat tax and is not refunded.)

Worked example 2: a 32%+ earner (under-withheld, owes more)

Now flip it. You're a high earner with a 32% marginal rate, and you receive a $20,000 bonus.

• Federal withholding at 22%: $20,000 x 0.22 = $4,400
• Your real federal tax at 32%: $20,000 x 0.32 = $6,400

Here the flat 22% withholding is too low. You were under-withheld by $6,400 - $4,400 = $2,000, and that shortfall is added to what you owe at filing. Many high earners are surprised by a bigger-than-expected tax bill precisely because the 22% flat rate didn't cover their true marginal rate. If that describes you, consider increasing regular withholding (a new Form W-4) or setting aside the difference so April isn't a shock.

The over-$1 million rule and other gotchas

The IRS applies a second, higher flat rate to large supplemental pay. Once your total supplemental wages for the year exceed $1 million, the portion above that threshold is withheld at the top rate of 37%, mandatory, no employer discretion. Below $1 million, the 22% method is the norm.

A few more things that trip people up:

• The "aggregate method." Some employers lump the bonus into a regular paycheck and withhold as if that combined amount were your normal pay. This can push withholding even higher than 22% temporarily. Either way, it's still just withholding, and still reconciled at filing.
• 401(k) and benefits. Depending on your plan, retirement contributions and other pre-tax deductions may or may not come out of a bonus, which changes the taxable amount.
• State tax. Don't forget it. The 29.65% federal estimate above is before your state takes its share.

The honest takeaway: withholding is not your tax

If your marginal rate is below 22%, the bonus was over-withheld and you'll likely recover the difference. If your rate is above 22%, you were under-withheld and should plan to owe more. The 22% on your check is a placeholder, your real tax depends on your total income for the year, your bracket, deductions, and credits, all settled when you file.

To see how the year-end reconciliation actually shakes out, model your full-year income with the tax estimator, and if you want to understand how the bonus interacts with your base pay over the year, the salary calculator helps you see the bigger picture. For a deeper walk-through of marginal rates, see our guide on what a tax bracket is.

These are estimates for planning, not tax advice. Brackets, the Social Security wage base, and supplemental rates change, so confirm current figures at IRS.gov or with a tax professional before making decisions.

Frequently Asked Questions