How Much Tax Is Taken Out of a Bonus Check? (2026)

A bonus check often disappoints on first sight: the net amount looks far smaller than the gross. Understanding why — and what you will actually owe versus what is just withheld upfront — helps you plan for the net amount you receive and avoid surprises when you file your annual return.

Two Federal Withholding Methods for Bonuses

When an employer pays a bonus separately from a regular paycheck, the IRS allows two withholding approaches. The flat-rate supplemental method applies a single withholding rate defined in IRS Publication 15 to the bonus amount — regardless of your W-4 filing status. The aggregate method combines the bonus with a recent regular paycheck and uses the standard annualized wage tables to determine withholding for the combined amount. Most employers use the flat-rate method for separately issued bonus checks. See IRS Publication 15 for the current flat supplemental rate.

FICA Applies to Bonuses

Social Security (6.2%) and Medicare (1.45%) apply to bonus payments just as they do to regular wages. For a modest bonus, expect both to be withheld in full. If your year-to-date wages have already passed the Social Security wage base before the bonus is paid, the Social Security portion of that bonus withholding will be zero — a welcome benefit for high earners receiving year-end bonuses.

State Withholding on Bonuses

State treatment of bonus withholding varies significantly. Some states apply their own supplemental withholding rate to bonuses paid separately. Others use the aggregate method. California has its own supplemental rate for bonuses. Texas and other no-income-tax states add no state withholding on bonus payments at all. Check your state's Department of Revenue for current guidance on how your state treats separately paid supplemental wages.

Engine-Derived Example: What Additional Income Produces

For a single filer in Texas earning a base salary of $100,000, the engine calculates annual take-home of $79,180. Modeling the same filer with $10,000 in additional income (representing a bonus effect on annual total) produces estimated take-home of $86,215. The net income from the additional $10,000 is approximately $7,035 — the rest goes to federal withholding and FICA. Your actual bonus check withholding will depend on which method your employer uses, but this comparison shows the effective tax cost of the additional gross income.

Why It Feels Over-Taxed — And Why It Isn't

The supplemental flat withholding rate is a payroll shortcut, not your actual marginal tax rate. If your regular income places you in the same bracket as the supplemental flat rate, you break even at filing. If your total income for the year is lower — for example, you received the bonus in a year when you worked only part-time — you may receive a refund because the flat rate over-withheld. If your total income pushes into a higher bracket, you may owe additional tax at filing beyond what was withheld.

Planning Around a Bonus

If you know a substantial bonus is coming, consider whether increasing your traditional 401(k) contribution for the remainder of the year could reduce your taxable income and lower the net additional tax owed. Pre-tax 401(k) contributions reduce federal taxable wages — though the supplemental withholding method may not reflect this during the pay period the bonus is issued. Model the full-year income impact by entering your total expected income (base + bonus) into the calculator and comparing it to your base salary scenario.

Model your take-home with your full expected annual income including bonus.

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Frequently Asked Questions

What is the supplemental wage withholding rate for bonuses?

The IRS sets a flat supplemental wage withholding rate for bonus payments issued separately from regular paychecks. For the current rate, check IRS Publication 15 — the flat rate is substantially lower than the top marginal income tax bracket but may still be higher than your marginal rate if you are a lower-income earner. See <a href="https://www.irs.gov/publications/p15">IRS Publication 15</a> for the rate applicable to your tax year.

Why does my bonus check look smaller than expected?

Bonuses paid separately from regular wages are typically subject to federal supplemental withholding, plus Social Security and Medicare, plus any state supplemental withholding. The combined withholding can make the check look heavily taxed — but withholding is not your final tax liability. At filing, you reconcile withholding against your actual marginal rate for the full year.

Can I get excess bonus withholding refunded?

Yes. Withholding is a prepayment toward your annual tax liability. If the supplemental rate applied to your bonus was higher than your actual marginal rate on that income, you receive a refund when you file. If your total income places you in a higher bracket than the supplemental rate, you may owe additional tax at filing.

What is the aggregate method for bonus withholding?

Under the aggregate method, your employer combines the bonus with your most recent regular paycheck, calculates withholding on the combined amount using the standard IRS tables, then subtracts the regular paycheck withholding. This can produce more or less withholding than the flat supplemental method depending on your salary level and pay frequency.

Figures and methods are based on official-source data encoded in the calculator. Not tax advice. Review the methodology and consult a qualified professional for your situation.