Georgia
Alabama
Kansas
MaineBonus $5,000
$3,270
State $247.50 · Total withheld $1,730
All states
2026Rank #24
2026Rank #24Illinois Bonus Tax 2026
~4.95% PIT — $495 state withholding, $6,540 net on $10,000 bonus with $80,000 year-to-date wages (flat supplemental method).
By Sammy S. · Founder · AuthorUpdated for 2026
~4.95% PIT
Rate
$495
State tax
$3,460
Total withheld
#24
National rank
Illinois bonus withholding at a glance
Supplemental rate
~4.95% PIT
State tax (vignette)
$495
Total withheld
$3,460
Net bonus
$6,540
No separate supplemental table; educational estimate uses the state’s flat PIT ≈4.95%. Rank #24 on $10,000 bonus with $80,000 year-to-date wages (flat supplemental method). Federal $2,200 + FICA $765 on this vignette.
Key takeaways — Illinois bonus tax
- Illinois ranks #24 at ~4.95% PIT (~$495 state tax on $10,000 bonus with $80,000 year-to-date wages (flat supplemental method)).
- Total vignette withholding ~$3,460 (federal $2,200 + FICA $765 + state $495); net ~$6,540.
- No separate supplemental table; educational estimate uses the state’s flat PIT ≈4.95%.
- Federal flat supplemental remains 22% regardless of state (IRS Pub. 15).
- Model custom amounts at /bonus-tax-calculator/illinois.
Illinois vs similar supplemental rates
States with supplemental rates closest to Illinois (~4.95% PIT). Illinois: $495 state tax on the vignette.
Modeled Illinois bonus stub ($10,000 bonus with $80,000 year-to-date wages (flat supplemental method))
Line amounts are calculated from our engine — the same engine as the bonus tax calculator. Not a substitute for your employer’s stub.
| Line | Amount | Note |
|---|---|---|
| Federal income tax (supplemental) | $2,200 | 22% flat (Pub. 15) on this vignette |
| FICA (SS + Medicare) | $765 | 6.2% SS + 1.45% Medicare (Additional Medicare if over $200k YTD) |
| IL state tax | $495 | ~4.95% PIT |
| Net bonus | $6,540 | After $3,460 total withheld |
Illinois withholding at different bonus sizes
Same $80,000 YTD wages; flat supplemental method. State rate ~4.95% PIT.
Bonus $10,000
$6,540
State $495 · Total withheld $3,460
Bonus $25,000
$16,350
State $1,237.50 · Total withheld $8,650
Bonus $50,000
$32,700
State $2,475 · Total withheld $17,300
How to read this page
Illinois bonus / supplemental withholding in 2026
No separate supplemental table; educational estimate uses the state’s flat PIT ≈4.95%.
On $10,000 with $80,000 YTD wages, modeled state withholding is $495 and take-home is about $6,540.
Compared with New York ($1,170 state) and Texas ($0 state) on the same vignette, Illinois sits at rank #24.
Illinois: flat PIT used as supplemental estimate
Illinois has a flat personal income tax and no separate supplemental percentage in our source set.
When a bonus is paid separately, many payroll systems withhold near the flat PIT of 4.95%. That is the educational estimate shown here.
County or local add-ons (where any) are not included.
How Illinois payroll usually handles bonuses
When the bonus is paid separately, many employers apply ~4.95% PIT state rules plus federal 22% and FICA.
If the bonus is combined with regular wages, withholding may follow the aggregate method instead of these flat percentages (IRS Pub. 15 §7).
Employees should reconcile annual liability on Form 1040 — paycheck withholding is only an estimate.
How withholding scales with bonus size
At a constant rate, state tax scales roughly linearly: double the bonus and state withholding roughly doubles (before exemptions or method changes).
Above $1M supplemental wages in a year with one employer, federal withholding jumps to 37% on the excess (Pub. 15).
What this profile does not include
Local city or municipal wage taxes (for example NYC resident tax, Philadelphia wage tax, Ohio city income tax) are not in these figures.
California SDI, state disability, paid family leave premiums, and local school taxes are outside the supplemental income-tax line.
Confirm current employer guides linked in the sources section before relying on a stub estimate.
Who this Illinois bonus page helps
Useful if…
- •Illinois employees reading a bonus stub
- •Candidates comparing Illinois offers to other states
- •Payroll teams verifying IL supplemental setup
Use official tools if…
- •City or local wage taxes not listed here
- •Signing bonuses paid with the first regular paycheck (aggregate method)
- •Year-end true-up if under-withheld at 22% federal
Illinois bonus withholding checklist
Quick steps before relying on this vignette for payroll decisions.
- 1Confirm Illinois’s current supplemental rule with the state tax agency.
- 2Ask payroll which withholding method they use for bonuses.
- 3Check federal, FICA, and state lines separately on the stub.
- 4Run scenarios at /bonus-tax-calculator/illinois.
- 5Plan estimated payments if your marginal bracket exceeds 22%.
Illinois bonus withholding ladder
| Bonus | State tax | Total withheld | Net |
|---|---|---|---|
| $5,000 | $247.50 | $1,730 | $3,270 |
| $10,000 | $495 | $3,460 | $6,540 |
| $25,000 | $1,237.50 | $8,650 | $16,350 |
| $50,000 | $2,475 | $17,300 | $32,700 |
Compare Illinois with another state
Compare any two states
Supplemental bonus withholding on a $10,000 bonus with $80,000 YTD wages.
Related states
Illinois bonus tax FAQs
Illinois has no separate supplemental table; our educational estimate uses the state’s flat PIT ≈4.95% (~$495 on $10,000 bonus with $80,000 year-to-date wages (flat supplemental method)).
On the vignette ($10,000 bonus, $80,000 YTD): about $3,460 total withheld ($2,200 federal + $765 FICA + $495 state), leaving ~$6,540 net (65.4% of gross).
With $80,000 year-to-date wages, a $5,000 bonus nets about $3,270 after roughly $1,730 withheld ($247.50 state).
With $80,000 year-to-date wages, a $25,000 bonus nets about $16,350 after roughly $8,650 withheld ($1,237.50 state).
With $80,000 year-to-date wages, a $50,000 bonus nets about $32,700 after roughly $17,300 withheld ($2,475 state). Enter your exact bonus and YTD wages at /bonus-tax-calculator/illinois for a personalized estimate.
Not necessarily. Flat 22% federal supplemental withholding (and 37% on supplemental wages over $1 million per employer per year) is a paycheck rule under IRS Publication 15. Your true federal tax depends on total annual income, deductions, and credits when you file Form 1040 — you may owe more or get a refund. Illinois state withholding at 4.95% is likewise an estimate against your full-year state liability.
Supplemental flat rates are a payroll shortcut when bonuses are paid separately. Employers may instead use the aggregate method (combine with regular wages). Confirm with payroll and your state withholding tables.
Usually yes under the flat supplemental method — signing, retention, and annual bonuses are all supplemental wages. Timing and whether payroll combines the payment with regular wages (aggregate method) can change the paycheck stub.
About $2,200 (22% flat) on this vignette — the same federal amount as in every other state — plus about $765 FICA (6.2% Social Security + 1.45% Medicare, subject to wage-base and Additional Medicare rules). The gap vs other states is almost entirely state supplemental withholding.
Social Security tax (6.2%) only applies until wages reach $184,500 in 2026. If year-to-date earnings plus the bonus cross that wage base, SS withholding on the bonus can be partial or zero. Medicare (1.45%) still applies with no wage base; an extra 0.9% Additional Medicare Tax can apply once wages exceed $200,000 for single filers (withholding threshold). Use /bonus-tax-calculator/illinois and the YTD field to model your situation.
Illinois ranks #24 of 51 jurisdictions for state supplemental withholding on the $10,000 vignette (~$495 state tax at 4.95%). Rank #1 is the highest state tax on that vignette.
Illinois withholds about $495 more in state tax than Texas ($0) on this vignette, so net take-home is about $495 lower ($6,540 vs $7,035). Federal and FICA are the same on the vignette.
It depends on your marginal federal bracket and full-year return. If your federal bracket is below 22%, flat supplemental withholding often over-withholds and you may get a refund. If your bracket is above 22%, you may owe more at filing. The same idea applies to Illinois state tax versus what was withheld at 4.95%.
This estimate covers Illinois state supplemental withholding (or $0 if none) plus federal and FICA. Local city wage taxes are not included unless your employer withholds them separately.
A gross-up means the employer increases the gross bonus so that after withholding you still receive a target net amount. Because Illinois adds about 4.95% state supplemental withholding, the gross needed to deliver a given net is higher than in no-tax states like Texas. Ask HR whether an offer is net or gross before you accept.
Under IRS Publication 15, supplemental wages over $1 million from the same employer in the same calendar year are withheld at 37% (mandatory flat rate) on the excess, while the first $1 million can use the 22% flat method. The $1 million threshold is per employer, per year — not combined across employers. Illinois state rules still apply on top.
Usually no under the flat supplemental method — both are supplemental wages. Timing and whether pay is combined with regular wages can change the stub via the aggregate method.
State income tax withheld may be itemized on Schedule A subject to the federal SALT cap. Whether you benefit depends on your full return.
About $2,200 (22% flat), the same as in every other state on this vignette — plus about $765 FICA.
Related topics
Illinois bonus tax calculator
Model any bonus amount and YTD wages
RSU tax by state
Same supplemental rates on RSU vests
RSU tax calculator
Same supplemental withholding rules at vest
Overtime pay by state
Daily OT rules that affect gross pay
Salary comparison by state
Take-home on regular wages
US paycheck calculator
Federal, state, and FICA take-home
Effective tax rate by state
Combined tax burden vignettes
State tax compare
Side-by-side state income tax