Bonus Calculator

Understanding employee bonuses and supplemental wage taxation

An employee bonus is additional compensation paid on top of regular wages to reward performance, celebrate company milestones, or incentivize talent retention. While receiving a bonus is an exciting financial event, many employees are surprised by how much smaller their net payout looks compared to their gross award.

The difference is driven by supplemental wage tax withholding rules. In the United States, the Internal Revenue Service (IRS) classifies bonuses, commissions, and severance as supplemental wages. Because these payouts do not follow standard periodic paycheck withholding brackets, employers typically apply a statutory flat federal withholding rate of 22% (or 37% on amounts exceeding $1,000,000), along with mandatory FICA taxes and state income taxes.

Whether you receive an annual performance incentive, a holiday bonus, or a signing bonus, this calculator estimates your exact take-home pay. To plan your regular ongoing earnings alongside your bonus, explore our biweekly pay calculator or 12-hour shift pay calculator.

How bonuses are calculated: 3 common structures

Employers structure bonus programs in different ways depending on industry norms, seniority, and performance metrics.

1. Percentage of base salary

Common in corporate and executive compensation, the bonus is tied directly to a contracted percentage of your annual base salary:

For example, an employee earning $90,000 with a 15% target bonus receives a gross bonus of:

2. Fixed dollar amount

Signing bonuses, spot recognition awards, referral fees, and holiday gifts are often awarded as a predetermined lump sum (for example, a flat $5,000 or $10,000 bonus), regardless of the employee's annual salary level.

3. Target bonus with performance multipliers

Many modern corporate bonus plans (such as Management by Objectives or corporate scorecard plans) use a multi-tiered formula that adjusts a target bonus percentage by company performance and individual achievement ratings:

If an employee earns $100,000 with a 10% target, and both the company and the individual achieved 110% of their annual targets, the resulting payout is:

How bonus taxes and withholdings work

Bonuses are fully subject to federal, state, and payroll taxes. However, tax withholding at payout time operates differently from standard payroll.

1. Federal income tax withholding (IRS supplemental rate)

Under IRS Publication 15-T (for the 2025 tax year), employers have two methods to calculate federal income tax withholding on supplemental wages:

• Percentage Method (Flat 22%): When supplemental wages are paid separately from regular wages, the employer withholds a flat 22% for amounts up to $1,000,000. Any portion of supplemental wages in excess of $1,000,000 is withheld at the highest individual tax bracket of 37%.
• Aggregate Method: The employer combines the bonus with regular pay for the pay period, calculates withholding as if that total were a normal paycheck, and subtracts the tax already withheld on regular pay. This can temporarily push the paycheck into a higher withholding bracket.

2. FICA payroll taxes (Social Security and Medicare)

Like all wage income, bonuses are subject to mandatory Federal Insurance Contributions Act (FICA) taxes:

• Social Security (OASDI): 6.2% on all earnings up to the annual Social Security wage base limit ($176,100 for the 2025 tax year). If your cumulative year-to-date earnings exceed this cap, no further Social Security tax is withheld from your bonus.
• Medicare (HI): 1.45% on all earnings with no wage cap, plus an Additional Medicare Tax of 0.9% on earnings exceeding $200,000 for single filers ($250,000 for married couples filing jointly).

3. State and local income taxes

Most states require state tax withholding on bonuses. Several states apply special supplemental rates (such as California at 6.6% or 10.23% for stock/bonuses, and New York at 11.70%), while states without earned income tax (such as Texas, Florida, Washington, Tennessee, and Nevada) withhold 0%. Local municipalities like New York City or Philadelphia also assess local wage taxes.

4. Pre-tax 401(k) and retirement contributions

Contributing a portion of your bonus to a traditional 401(k) reduces your gross taxable bonus dollar-for-dollar for federal and state income taxes. However, 401(k) contributions do not reduce FICA taxes. You can simulate long-term compound growth of these allocations with our 401(k) calculator.

Step-by-step worked example

Let us examine a real-world scenario. An employee with an $85,000 salary receives a 15% annual bonus ($12,750 gross). They elect to contribute 10% to their traditional 401(k), live in a state with a 5% tax withholding rate, and have not yet reached the Social Security wage cap:

In this example, the total taxes withheld equal $4,073.63 (31.95% effective tax rate), pre-tax savings equal $1,275.00 (10.00%), and the employee receives $7,401.37 in take-home cash (58.05% of gross bonus).

Tax withholding vs actual tax liability

A common misconception is that bonuses are taxed at a permanently higher rate than regular income. In reality, withholding is simply an upfront estimate sent to the IRS. At tax filing time, your bonus is combined with your base salary, self-employment income (which you can evaluate on our 1099 tax calculator), and investment gains to determine your final adjusted gross income (AGI).

If the 22% flat withholding rate exceeded your true effective federal tax bracket, you will receive the excess back as a tax refund. Conversely, if you are in the 32%, 35%, or 37% marginal brackets, the 22% withholding may be insufficient, meaning you could owe additional tax when filing your annual return.

Smart financial strategies for your bonus

A bonus provides a powerful liquidity boost that can accelerate your long-term wealth building:

• Boost Retirement Contributions: Allocating bonus funds into your 401(k) or IRA lowers your current-year tax burden and harnesses compound interest.
• Eliminate High-Interest Debt: Applying bonus cash to credit cards or personal loans delivers an immediate, risk-free return equal to the interest rate saved.
• Follow a Structured Budget: Allocate your take-home bonus across needs, wants, and savings using our 50/30/20 budget calculator.

Frequently asked questions