Wisconsin Bonus Tax Calculator 2026
Wisconsin's approved bonus rate depends on your annual salary: 5.30% for salaries from $25,520 to $280,950, and 7.65% above that.
Bonus check calculator
Flat percentages tied to salary
Wisconsin's Withholding Tax Guide (Publication W-166, 1/26) allows the usual aggregate methods and, "as an alternative," withholding on supplemental payments "by estimating the employee's annual gross salary and applying flat percentages." The approved percentages are 3.54% for salaries under $12,760, 4.65% under $25,520, 5.30% under $280,950 and 7.65% at $280,950 or more. They "may be used only where supplemental payments are involved."
Where the salary line falls
The standard example's $78,000 salary is in the 5.30% band, so a $5,000 bonus carries $265.00. The same bonus to someone earning $300,000 is withheld at 7.65% — $382.50 — and to a part-time employee earning $23,400 a year ($900 every two weeks) at 4.65%, $232.50. The calculator estimates annual salary from the regular pay you enter.
The other two options
W-166 also allows the familiar aggregate approaches: if a bonus is paid with regular wages, withhold on the total as one payment; if it is paid between paydays, add it to the current or last preceding regular payroll and withhold the difference. For the standard employee, a $20,000 bonus under the flat-percentage option is withheld $1,060.00 at 5.30%.
| Rule | Flat percentage set by annual salary: 3.54%, 4.65%, 5.30% or 7.65% |
|---|---|
| Valid through | December 31, 2026 |
| Documents | Publication W-166 Withholding Tax Guide ((1/26)) |
| Agency | Wisconsin Department of Revenue |
| Federal income tax | −$1,100.00 |
| Social Security | −$310.00 |
| Medicare | −$72.50 |
| Wisconsin income tax | −$265.00 |
| Net | $3,252.50 |