📊 Illinois Income Tax Calculator 2026
Calculate your Illinois state income tax with our free calculator. Accurate 2026 tax brackets, standard deductions, and credits. See your exact IL tax liability.
Calculate Your Illinois Income Tax
Tax Bracket Breakdown
2026 Illinois Tax Brackets
Illinois has one of the highest state income tax rates in the nation, with a top marginal rate of 4.95% for high earners. The state uses a progressive tax system with 10 tax brackets.
| Taxable Income (Single) | Tax Rate | Tax Owed |
|---|---|---|
| $0 - $10,412 | 1.0% | Up to $104 |
| $10,413 - $24,684 | 2.0% | $104 + 2% of excess |
| $24,685 - $38,959 | 4.0% | $389 + 4% of excess |
| $38,960 - $54,081 | 6.0% | $960 + 6% of excess |
| $54,082 - $68,350 | 8.0% | $1,867 + 8% of excess |
| $68,351 - $349,137 | 9.3% | $3,009 + 9.3% of excess |
| $349,138 - $418,961 | 10.3% | $29,122 + 10.3% of excess |
| $418,962 - $698,271 | 11.3% | $36,313 + 11.3% of excess |
| $698,272 - $1,000,000 | 12.3% | $67,855 + 12.3% of excess |
| $1,000,001+ | 4.95% | $104,968 + 4.95% of excess |
Married Filing Jointly brackets are exactly double the Single brackets (e.g., first bracket is $0-$20,824 @ 1%).
Illinois Standard Deduction (2026)
- Single / Married Filing Separately: $5,363
- Married Filing Jointly: $10,726
- Head of Household: $10,726
Illinois does NOT allow federal itemized deductions — you must use the state standard deduction. However, you can claim additional deductions for dependents, mortgage interest, and charitable contributions on Schedule IL.
How Illinois Income Tax Works
Illinois uses a progressive tax system where your income is taxed at different rates as it climbs through the brackets. Only the income in each bracket is taxed at that bracket's rate.
Example: $75,000 income (Single filer)
- Gross income: $75,000
- Standard deduction: -$5,363
- Taxable income: $69,637
- Tax calculation:
- First $10,412 @ 1% = $104
- Next $14,272 @ 2% = $285
- Next $14,275 @ 4% = $571
- Next $15,122 @ 6% = $907
- Next $14,269 @ 8% = $1,142
- Remaining $1,287 @ 9.3% = $120
- Total IL tax: $3,129
- Effective rate: 4.17% (even though top bracket is 9.3%)
Illinois vs Federal Income Tax
You pay BOTH federal and Illinois state income tax on your earnings. Here's how they compare:
| Income Level | Federal Tax | IL State Tax | Combined |
|---|---|---|---|
| $50,000 (Single) | ~$4,200 (8.4%) | ~$1,700 (3.4%) | ~11.8% |
| $100,000 (Single) | ~$14,000 (14%) | ~$5,900 (5.9%) | ~19.9% |
| $200,000 (Single) | ~$38,000 (19%) | ~$15,400 (7.7%) | ~26.7% |
| $500,000 (Single) | ~$140,000 (28%) | ~$43,000 (8.6%) | ~36.6% |
| $1,000,000 (Single) | ~$330,000 (33%) | ~$105,000 (10.5%) | ~43.5% |
Illinois's top earners pay some of the highest combined tax rates in the U.S. — up to 50%+ when including federal, state, and payroll taxes.
Illinois Tax Credits
Illinois offers several tax credits that can reduce your tax liability:
- Earned Income Tax Credit (IL EITC) — Up to $3,417 for low-income workers with children
- Young Child Tax Credit (YCTC) — $1,117 per child under 6 (income limits apply)
- Renters' Credit — $60 (single) or $120 (married) if you rent and meet income limits ($51,983 single, $103,966 married)
- Senior Head of Household Credit — $1,358 for seniors 65+ who are head of household
- Dependent Parent Credit — $593 for supporting a parent aged 65+ living with you
- Child Adoption Costs Credit — Up to $2,500 per child for qualified adoption expenses
Illinois Tax Filing Deadlines
- Tax Day: April 15, 2026 (state deadline matches federal)
- Extension Deadline: October 15, 2026 (automatic 6-month extension available)
- Q1 Estimated Tax: April 15, 2026
- Q2 Estimated Tax: June 15, 2026
- Q3 Estimated Tax: September 15, 2026
- Q4 Estimated Tax: January 15, 2027
Extensions to file are NOT extensions to pay. You must estimate and pay your tax by April 15 to avoid penalties, even if you file your return later.