Illinois state taxes at a glance
| Individual income tax | Flat-rate income tax |
|---|---|
| Rate structure | A flat individual income tax rate (4.95% as of our latest review). The state constitution requires a uniform rate; Illinois does not have brackets. |
| Tax agency | Illinois Department of Revenue (IDOR) |
| Main individual return | Form IL-1040 |
| Local income taxes | No general local income taxes (Chicago has other local taxes, such as on certain transactions). |
| Sales tax | A state rate plus home-rule and local add-ons, so combined rates vary widely; some items, such as qualifying groceries, are taxed at a lower rate. |
| Property tax | Locally administered; Illinois property taxes are among the highest in the country as a share of home value. Credits and exemptions exist; check with your county. |
| Retirement & Social Security | Illinois generally does not tax Social Security benefits or most qualified retirement income such as pensions and IRA distributions. |
Verify current-year figures: state rates, brackets, credits and filing rules change. Treat this page as a starting orientation and confirm details on the Illinois Department of Revenue (IDOR) website.
How Illinois income tax works
Illinois’ constitution requires income to be taxed at a single non-graduated rate, so every filer pays the same percentage on taxable income, after subtracting an exemption allowance for you, your spouse and dependents (subject to income limits). The state starts from your federal adjusted gross income, then applies its own additions and subtractions, such as exempting most retirement income and Social Security.
Illinois has a few credits worth checking: a property tax credit for a share of the property tax you paid on your principal residence (income limits apply), an education expense credit for certain K-12 expenses, and a state earned income credit tied to the federal credit. Details and caps change, so verify them on the Department of Revenue site. Our federal guides to the EITC and standard deduction explain the federal side.
Because the rate is flat, state planning is simpler than in states with brackets — but the interaction with federal rules still matters. The state does not follow every federal deduction, and the Illinois subtractions and additions on Schedule M are where many errors happen.
Filing your Illinois return and free options
Residents file Form IL-1040 by April 15. The state’s MyTax Illinois portal is used for filing, payments, refund status and account management, and has historically allowed eligible individuals to file a basic return directly with the state. Confirm what is currently free on the IDOR website, and see our free filing options hub for the federal side.
If you moved to or from Illinois, you generally file Schedule NR to allocate income. Illinois also has its own payment plan options if you cannot pay in full — contact IDOR early, as with the IRS (see what if you can’t pay your taxes).
For the federal side, see our guides to free federal filing options and the complete guide to filing taxes.
Things Illinois residents often ask about
- Property tax credit: claim it on the IL-1040 if you qualify, using Schedule ICR; keep your property tax bills.
- Retirement income: subtract qualifying retirement income on Schedule M; don’t assume your software did.
- Illinois has no local income tax, but a Chicago employee may see other local taxes elsewhere in their finances; those are not on your income tax return.
- Refund status: use MyTax Illinois; see state refund status.
Official Illinois links
- Illinois Department of Revenue
- MyTax Illinois (portal)
- IDOR: individuals
- Federation of Tax Administrators: State tax agencies
Frequently asked questions
What is the Illinois income tax rate?
A flat rate (4.95% as of our latest review). Confirm the current rate on tax.illinois.gov.
Does Illinois tax retirement income?
Illinois generally exempts Social Security and most qualified retirement income. Other income, like wages and interest, is taxed.
Where do I check my Illinois refund?
Through MyTax Illinois on the Department of Revenue website.
General information only — not tax, legal or financial advice. Tax figures change every year; verify the current numbers at IRS.gov or with a qualified professional. Read the full disclaimer.