Table of Contents
Illinois State Income Tax
Illinois is one of the states that uses a flat income tax rate, which means all taxpayers pay the same percentage regardless of income level. The current Illinois state income tax rate is 4.95% as of 2024.
This flat tax system makes Illinois taxes relatively simple to calculate compared to states with progressive income tax rates. However, it also means lower-income earners pay the same rate as higher earners, which some consider regressive.
Illinois Tax Exemptions
Illinois allows personal exemptions that reduce your taxable income:
- Single filer: $2,625 per exemption (2024)
- Married filing jointly: $2,625 per person
- Dependents: Additional $2,625 per dependent
Illinois Tax = (AGI - Exemptions) × 4.95%
Where AGI = Adjusted Gross Income
No Local Income Tax
Unlike some states, Illinois does not allow cities or counties to impose their own income taxes. This means you only pay state-level income tax, not additional local taxes on your earnings.
Federal Income Tax Brackets (2024)
Federal income tax uses a progressive system with seven tax brackets. You only pay the higher rate on income that falls within each bracket.
Single Filers
| Tax Rate | Income Range |
|---|---|
| 10% | $0 - $11,600 |
| 12% | $11,601 - $47,150 |
| 22% | $47,151 - $100,525 |
| 24% | $100,526 - $191,950 |
| 32% | $191,951 - $243,725 |
| 35% | $243,726 - $609,350 |
| 37% | $609,351+ |
Married Filing Jointly
| Tax Rate | Income Range |
|---|---|
| 10% | $0 - $23,200 |
| 12% | $23,201 - $94,300 |
| 22% | $94,301 - $201,050 |
| 24% | $201,051 - $383,900 |
| 32% | $383,901 - $487,450 |
| 35% | $487,451 - $731,200 |
| 37% | $731,201+ |
Standard Deductions (2024)
- Single: $14,600
- Married Filing Jointly: $29,200
- Married Filing Separately: $14,600
- Head of Household: $21,900
FICA Taxes (Social Security & Medicare)
FICA taxes fund Social Security and Medicare programs. All wage earners pay these taxes regardless of income level.
Social Security Tax
- Rate: 6.2% of wages
- Wage Base Limit (2024): $168,600
- Maximum Tax: $10,453.20
You only pay Social Security tax on the first $168,600 of wages. Income above this amount is not subject to Social Security tax.
Medicare Tax
- Rate: 1.45% of all wages
- Additional Medicare Tax: 0.9% on wages over $200,000 (single) or $250,000 (married)
Unlike Social Security, there is no wage limit for Medicare tax.
Social Security = Wages × 6.2% (up to $168,600)
Medicare = Wages × 1.45% (+ 0.9% on high earners)
Total FICA = Social Security + Medicare
Deductions and Exemptions
Understanding deductions can significantly reduce your tax liability.
Federal Deductions
You can choose between the standard deduction or itemizing deductions (whichever gives you the larger benefit):
- Standard Deduction: A fixed amount based on filing status
- Itemized Deductions: Include mortgage interest, state/local taxes (SALT, capped at $10,000), charitable contributions, medical expenses (above 7.5% AGI)
Pre-Tax Contributions
Contributions to qualified retirement accounts reduce your taxable income:
- 401(k): Up to $23,000 (2024), or $30,500 if over 50
- Traditional IRA: Up to $7,000 (2024), or $8,000 if over 50
- HSA: Up to $4,150 (individual) or $8,300 (family)
Illinois Property Tax
While this calculator focuses on income taxes, it's worth noting that Illinois has some of the highest property taxes in the nation.
- State Average: Approximately 2.07% of assessed value
- Highest Counties: Lake County (2.95%), McHenry County (2.80%)
- Cook County: Varies significantly by municipality
Tax Calculation Examples
Example 1: Single Filer, $60,000 Income
Standard Deduction: $14,600
Taxable Income: $60,000 - $14,600 = $45,400
Tax: $1,160 + 12% × ($45,400 - $11,600) = $1,160 + $4,056 = $5,216
Illinois Tax:
Exemption: $2,625
Taxable: $60,000 - $2,625 = $57,375
Tax: $57,375 × 4.95% = $2,840
FICA: $60,000 × 7.65% = $4,590
Total Tax: $12,646
Take-Home: $47,354
Example 2: Married Filing Jointly, $100,000 Income
Standard Deduction: $29,200
Taxable Income: $100,000 - $29,200 = $70,800
Tax: $2,320 + 12% × ($70,800 - $23,200) = $2,320 + $5,712 = $8,032
Illinois Tax:
Exemptions (2): $5,250
Taxable: $100,000 - $5,250 = $94,750
Tax: $94,750 × 4.95% = $4,690
FICA: $100,000 × 7.65% = $7,650
Total Tax: $20,372
Take-Home: $79,628
Tax Planning Tips for Illinois Residents
401(k) and IRA contributions reduce both federal and state taxable income. Contributing the maximum can save thousands in taxes annually.
Health Savings Accounts offer triple tax benefits: tax-deductible contributions, tax-free growth, and tax-free withdrawals for qualified medical expenses.
If your itemized deductions exceed the standard deduction, keep records of mortgage interest, charitable donations, and state/local taxes paid.
If you expect to be in a different tax bracket next year, consider timing income and deductions to minimize your overall tax burden.
Frequently Asked Questions
Does Illinois have a progressive income tax?
No, Illinois has a flat income tax rate of 4.95%. All taxpayers pay the same rate regardless of income level. A 2020 ballot measure to switch to a progressive system was rejected by voters.
Are there any local income taxes in Illinois?
No, Illinois does not permit cities or counties to levy their own income taxes. You only pay state-level income tax.
What is the Illinois personal exemption?
For 2024, the personal exemption is $2,625 per person. This includes the taxpayer, spouse (if filing jointly), and dependents.
Is Social Security income taxed in Illinois?
No, Illinois does not tax Social Security benefits. However, Social Security may be partially taxable on your federal return depending on your total income.
How do I estimate my quarterly tax payments?
If you're self-employed or have significant non-wage income, divide your estimated annual tax liability by 4 and pay quarterly. Use this calculator to estimate your total tax, then divide by 4.
What happens if I work remotely for an out-of-state company?
If you live in Illinois, you generally pay Illinois state tax on your income regardless of where your employer is located. However, you may need to file returns in multiple states if you physically work in another state.