Estimate tax on bonus in Illinois.
Bonuses are often taxed as supplemental income at a flat rate. Tax is estimated in Illinois by applying the rate you enter.
Tax
Tax = bonus × rate
Estimate only.
For supplemental income such as bonuses many employers use a flat 22% federal rate; other situations vary.
Rates are approximate reference values. Local rates, exemptions and rules can differ, so treat the output as a planning figure only.