Illinois Tax Brackets 2025 Guide – Illinois uses a flat income tax system instead of progressive tax brackets like the federal government. This comprehensive guide covers everything Illinois residents and taxpayers need to know about state taxes for the 2025 tax year (returns filed in 2026), including the current rate, exemptions, calculation steps, filing requirements, and comparisons to federal brackets. All information comes directly from official Illinois Department of Revenue (IDOR) sources.
Illinois Income Tax Rate 2025: Flat Rate Confirmed
Illinois does not have traditional progressive tax brackets for individual income tax. The state applies a single flat rate of 4.95% to net income. This rate has remained unchanged since July 1, 2017.
This flat structure simplifies tax planning compared to states with multiple brackets. Whether you earn $50,000 or $500,000, the state tax rate on taxable net income stays the same (subject to exemptions and modifications).
How to Calculate Your Illinois State Income Tax in 2025
Follow these steps using your federal return as the starting point:
- Begin with your federal adjusted gross income (AGI).
- Add Illinois-specific additions (e.g., tax-exempt interest, certain partnership losses, special depreciation, or prior-year 529/ABLE recapture—reported on Schedule M).
- Subtract Illinois-specific subtractions (e.g., Social Security benefits, qualifying retirement income like IRAs, pensions, and government annuities—also on Schedule M).
- The result is your Illinois base income.
- Subtract your personal exemption allowance (see next section) to arrive at net income.
- Multiply net income by 4.95% to get your Illinois income tax.
Nonresidents and part-year residents use Schedule NR and pay tax only on Illinois-source income.
Personal Exemption Allowance 2025: How Much You Can Subtract
For tax year 2025, the base personal exemption is $2,850 per person (you, spouse, and each dependent).
- Add $1,000 per qualifying person who is age 65 or older.
- Add $1,000 per qualifying legally blind person.
Important phase-out rule: The exemption allowance drops to zero if your federal AGI exceeds:
- $250,000 (single, head of household, married filing separately, or qualifying surviving spouse)
- $500,000 (married filing jointly)
Dependents claimed on your return may still require a separate filing if their base income exceeds the exemption amount.
What Income Does Illinois Tax? Key Subtractions and Additions
Illinois taxes most wage, salary, business, and investment income at the flat 4.95% rate. However, it offers generous subtractions that many other states do not:
- Social Security benefits (fully exempt).
- Qualifying retirement income (IRAs, 401(k)s, pensions, annuities, and certain government plans).
- Illinois income tax refunds from prior years.
Additions are less common but include items like federally tax-exempt interest or certain out-of-state adjustments. Full details appear in Schedule M of Form IL-1040.
Illinois does not tax:
- Social Security
- Most retirement distributions
- Certain municipal bond interest (with exceptions)
Illinois Tax Filing Requirements and Deadlines 2025
Who must file?
- Illinois residents who are required to file a federal return or have Illinois base income greater than their exemption allowance.
- Nonresidents or part-year residents with Illinois-source income (or to claim a refund of withheld tax).
- Dependents if their base income exceeds $2,850.
Deadline: April 15, 2026 (for calendar-year filers).
An automatic 6-month extension to October 15, 2026, is available, but you must still pay any tax owed by April 15 to avoid penalties. File electronically through MyTax Illinois for the fastest refunds.
Illinois vs. Federal Tax Brackets 2025: Side-by-Side Comparison
Many people search for “Illinois tax brackets 2025” and expect progressive rates. Here’s how Illinois compares to the federal system (which does use brackets):
Federal 2025 Tax Brackets (for reference):
- 10%: $0–$11,925 (single)
- 12%: $11,926–$48,475
- 22%: $48,476–$103,350
- 24%: $103,351–$197,300
- 32%: $197,301–$250,525
- 35%: $250,526–$626,350
- 37%: Over $626,350
(Married filing jointly brackets are roughly double.)
Illinois: Flat 4.95% on net income after exemptions—no brackets at all. Your effective state rate is almost always lower than your top federal marginal rate.
Other Illinois Taxes You Should Know in 2025
- Sales tax: State base rate is 6.25%, with local add-ons pushing combined rates as high as 11% in some areas.
- Property tax: Illinois has one of the highest effective property tax rates in the U.S. (around 1.88% of assessed value on average).
- Corporate income tax: 7% flat rate (higher than individuals).
- Gambling/lottery withholding: 4.95% on certain winnings.
Tax Tips for Illinois Residents Filing in 2026
- Maximize retirement contributions (they reduce federal AGI and often Illinois base income).
- Claim all available credits: Illinois Earned Income Tax Credit (EITC), Child Tax Credit (40% of EITC for qualifying children), and property tax credits.
- Use MyTax Illinois for free electronic filing and direct deposit.
- Track out-of-state purchases for Use Tax if not taxed at point of sale.
- Consult a tax professional if your AGI is near phase-out thresholds or you have complex investments.
Frequently Asked Questions About Illinois Tax Brackets 2025
Does Illinois have tax brackets in 2025?
No. Illinois uses a flat 4.95% rate on net income.
Is Social Security taxed in Illinois?
No—fully exempt.
When is the 2025 Illinois tax return due?
April 15, 2026.
How much is the personal exemption in Illinois for 2025?
$2,850 base amount per person, with additional amounts for seniors and the blind (subject to AGI phase-out).
For the most accurate and personalized advice, always refer to the official Illinois Department of Revenue website or consult a qualified tax advisor. Tax laws can change, and your individual situation may vary. File early and electronically to avoid delays and maximize your refund.
This guide was updated with the latest official information available for tax year 2025. Stay informed by checking tax.illinois.gov directly.