Illinois Bonus Tax Calculator (2026)
Illinois withholds 4.95% state income tax on bonuses, on top of the federal 22% and 7.65% FICA.
Illinois rules for bonuses
Regular withholding (aggregate method).
- IL-700-T (2026) has no supplemental section; flat 4.95% after allowances
- 86 Ill. Adm. Code 100.7050 reportedly follows federal methods (unconfirmed, header #8)
Generally, the rate for withholding Illinois Income Tax is 4.95 percent.
Local taxes: None
Take-home bonus by amount
| Bonus | Federal (22%) | FICA | State | Take-home |
|---|---|---|---|---|
| $1,000 | $220 | $77 | $50 | $654 |
| $2,500 | $550 | $191 | $124 | $1,635 |
| $5,000 | $1,100 | $383 | $248 | $3,270 |
| $10,000 | $2,200 | $765 | $495 | $6,540 |
| $20,000 | $4,400 | $1,530 | $990 | $13,080 |
| $50,000 | $11,000 | $3,825 | $2,475 | $32,700 |
Sources
Frequently asked questions
What is the bonus tax rate in Illinois?
Illinois withholds 4.95% on bonuses, on top of the federal 22% and 7.65% FICA.
How much of a $10,000 bonus do I keep in Illinois?
About $6,540 for a single filer earning $85,000: $2,200 federal, $765 Social Security and Medicare and $495 state.
Will I get some of the bonus tax back?
Possibly. The 22% federal rate is only withholding. At tax time your bonus is taxed at your bracket (22% at this salary), and Illinois's flat supplemental rate can also differ from your actual state rate.