Commission tax calculator
Federal table verified 2026-08-15. State supplemental table verified 2026-08-29.
A commission is a supplemental wage. IRS Publication 15 lists commissions next to bonuses and overtime as wage payments that aren't regular wages. Paid on its own check, or on a combined check with each amount shown separately, an employer that withheld income tax from your regular wages in the current or preceding calendar year can withhold a flat 22% of it for federal income tax, and Publication 15 allows no other percentage under that option. Folded into a regular check with no split shown, the whole check is withheld on as one regular payroll payment (same source).
Social Security and Medicare come out either way, since Publication 15 says supplemental wages carry those taxes whichever income-tax method the employer uses. Your state adds its own line, and that's where the spread lives. The table below the tool covers 30 of 51 jurisdictions with a supplemental rule checked against the state's own guide or statute for tax year 2026. Put your figures in and the tool shows the flat method, the aggregate method, the gap between them, and which way that gap points when you file. Every state gets a state line: the verified supplemental rate where the state publishes one, and otherwise a labelled estimate from the site's own state table, so the net figure is never left blank.
Estimate withholding on this commission check
Regular wages start prefilled from the BLS QCEW average annual pay for the United States, $78,722 (QCEW US), split by pay frequency. Pick California, New York, Texas or Florida and the box switches to that state's series figure, $96,946 for California (QCEW CA), $99,949 for New York (QCEW NY), $77,995 for Texas (QCEW TX) and $72,770 for Florida (QCEW FL).
Not tax, legal, or financial advice. Estimate only. Excludes pre-tax deductions, local taxes, and credits. Verify with your employer or a qualified professional. Tax data last verified August 2026.
A worked example from the same tables
Take a $5,000.00 commission paid on its own check to someone filing jointly in California, with regular wages prefilled from the BLS national average, $3,028.00 every two weeks. The flat method withholds $1,100.00 of federal income tax at 22%, Social Security takes $310.00, Medicare $72.50, and California's 6.6% supplemental rate takes $330.00, so $3,187.50 lands in the account. Run the brackets on the year with and without that commission and it adds $600.00 of federal tax, which is $500.00 less than the flat method withheld. That gap is the number the tool prints on the reconciliation line for your own figures, and it flips sign once regular wages push the commission into a bracket above the flat rate. Every figure in this paragraph is recomputed from the injected tables when the page loads.
State supplemental withholding rates for tax year 2026
Each row was read from that state's own withholding guide or statute, and the source sits in the row. Only rows the dataset marks verified appear, plus the states with no wage income tax; unverified states stay out, and the caption names the count over all jurisdictions so the coverage is plain. Where a state runs supplemental wages through its regular tables, the row says so instead of showing a rate.
Methodology
Every figure on this page is computed in the browser from two data objects injected at build time, and none of them is typed into the text. The federal object carries the year's brackets, standard deduction, the optional and mandatory supplemental rates, and the FICA rates and wage base. I cross-check it against Publication 15 section 7 for the supplemental rules, Publication 15-T for the percentage method, and Tax Topic 751 for the FICA rates. Topic 751 puts Social Security at 6.2% for the employee and the same for the employer, with a wage base of $184,500.00 for the year (Topic 751), and says only Social Security has a base while Medicare has none (Topic 751). The Additional Medicare Tax of 0.9% is withheld on wages over the threshold without regard to filing status (Topic 751), and Publication 15 says there's no employer share of it.
The state object holds one row per jurisdiction with the method, the rate where a state publishes one, and the URL of the primary source it was read from. The tool uses a row only when its status is verified or no income tax; anything else falls back to the site's general state table and prints the word estimate on the line. The prefilled regular wages come from the BLS average annual pay series, which the site publishes only when two separate BLS endpoints return the same value. When I wired that feed, the average-weekly-wage series turned out to publish quarterly only, so a weekly-wage cross-check silently returned nothing, and I dropped it for the annual series.
The aggregate estimate multiplies the pay period's wages by the number of pay periods, the same first step Worksheet 1A in Publication 15-T takes, then subtracts the standard deduction, runs the brackets, and divides back to one period. The worksheet's own adjustment lines differ from a plain standard deduction, so read the aggregate figure as an estimate of what a payroll system produces, not a reproduction of it. The flat figure is simpler, and Publication 15-T says its withholding methods can't be used at all when the optional flat rate or the mandatory top rate applies to supplemental wages.
Questions people ask about commission withholding
Separate check or combined with regular wages
Ask payroll which way they cut it, because the method follows the check. Separately paid, or combined with each amount shown, and Publication 15 allows the flat rate, but only if income tax was withheld from your regular wages in the current or immediately preceding calendar year. If it wasn't, the aggregate method is required (Publication 15). Under that method the employer adds the commission to the wages from the most recent regular pay date, figures withholding on the combined amount, and subtracts what was already withheld on the regular wages (Publication 15, method 1b).
Why the withholding feels high
Two mechanisms do it. The flat rate skims one percentage off the top with no look at your regular pay. The aggregate method annualizes the period, and Worksheet 1A multiplies one period's wages by the number of pay periods in the year, so a single large commission gets projected as if you earned it every period. Either way, withholding is a deposit toward the year's tax rather than the tax itself, and the reconciliation line in the tool shows which direction the gap points.
Commission and bonus on the same check
Both are supplemental wages under Publication 15, so the same method choice covers the combined amount on the check. Both also count toward the year's supplemental total for the million-dollar test, which Publication 15 measures by adding the payment to the other supplemental wage payments made to you during the calendar year.
The million-dollar rule
Once supplemental wages paid to you in a calendar year pass $1,000,000.00, the excess is withheld at 37% without regard to your Form W-4 (Publication 15). The count includes payments from all businesses under common control (Publication 15). The tool applies the top rate only to the portion over the line, which is why the optional field for supplemental wages already paid this year matters if you're anywhere near it.
How states differ
Federal rules are one set; state rules are one set per jurisdiction, and they don't rhyme. Some states publish a flat supplemental rate. California's sits in statute, Revenue and Taxation Code section 18663, at 6.6% in lieu of the wage withholding tables (Cal. RTC 18663). New York's rate for bonuses and commissions paid separately is 11.7%, effective the start of the tax year (NYS-50-T-NYS). Others have no wage income tax at all, among them Texas (Texas Comptroller), Florida (Florida Department of Revenue), Washington (RCW 1.90.100) and Nevada (Nevada Department of Taxation). A few run everything through their regular method. Connecticut says there is no percentage method for its wage withholding (CT IP 2026(1)), and Pennsylvania withholds on compensation, supplemental included, at its single flat rate (REV-415). Some key off the federal choice. Iowa requires its highest individual rate on supplemental wages whenever federal withholding used a flat rate (Iowa Department of Revenue), New Mexico does the same with its own flat rate (FYI-104), and Wisconsin tiers its approved flat percentages by the employee's annual gross salary (Publication W-166).
Reconciliation when you file
Withholding today isn't your final tax. The tool runs the bracket engine on your annual regular wages alone and again with the commission added; the difference is the federal tax the commission adds for the year, assuming level pay and the standard deduction. Set that against the amount withheld and you have the gap. Over-withheld points toward a refund, under-withheld toward an amount still owed, and a commission withheld at the flat rate lands on one side or the other depending on whether your marginal bracket sits above or below that rate. The bracket bands come from the injected federal table and follow the percentage method in Publication 15-T, which it says works for any amount of wages.