Illinois Tax Calculator
The Illinois (IL) Tax Calculator is updated for the 2026/27 tax year. Illinois applies a flat-rate state income tax. This tool estimates your Illinois state tax alongside federal income tax, Social Security, and Medicare to show projected take-home pay.
Quick Access Tools
Quick Illinois Tax Calculator
Enter income and filing status, then select Calculate for instant results. Use tabs to add itemized deductions, dependents, retirement deferrals, and withholdings. Illinois has no local wage income tax; leave Local Taxes off unless modeling a custom scenario.
Input key: F Used in Federal tax calculations S Used in State tax calculations
How to Calculate Income Tax in Illinois for 2026/27
- Enter your gross annual income and any adjustments.
- Choose your filing status (Single, Married filing jointly, etc.).
- Click Calculate to view Illinois state tax, federal taxes, FICA/Medicare, and take-home pay.
Advanced Options
- Compare itemized deductions with the federal standard deduction.
- Model IRA/401(k) deferrals and other pre-tax benefits.
- Add dependents to reflect child-related credits.
- Enter withholdings (federal, state, Medicare, Social Security) to project refund or balance due.
Related Calculators
Common Illinois Forms & Schedules
Browse the essential Illinois (IL) tax forms used for personal and business income tax filing. Common examples include Form IL-1040 (Individual Income Tax Return) and Schedule M (Other Additions and Subtractions), along with credits, withholding, and estimated payment schedules supporting Illinois taxpayers.
- Illinois Form IL 1040 Individual Income Tax Return
- Illinois Form IL 1040 Schedule G Voluntary Charitable Donations
- Illinois Form IL 1040 Schedule M Additions and Subtractions
- Illinois Form IL 1040 Schedule NR Nonresident and Part-Year Resident
- Illinois Form IL 1040 Schedule ICR Illinois Credits
- Illinois Form IL 1040 Schedule CR Credit for Tax Paid to Other States
- Illinois Form IL 1040 Schedule IL E EITC Earned Income Credit
- Illinois Form IL 1040 X Amended Individual Income Tax Return
- Illinois Form IL 1040 Schedule 1299 A Tax Subtraction and Credit Summary
- Illinois Form IL 4562 Depreciation and Amortization Adjustments
- Illinois Form IL 1299 C Tax Credit Recapture Schedule
Additional Resources
- All State Calculators
- Federal and State Tax Tables
- Federal Income Tax Calculator
- Report an issue or request a correction
Frequently Asked Questions
Quick answers for Illinois filers: flat-rate state tax, federal coordination, deductions, dependents, and withholdings.
Why is Schedule 1299-C important for transparency?
It maintains fairness within Illinois’s incentive programs. By recapturing credits when eligibility changes, the state ensures that incentives reward long-term economic activity rather than short-term gains. For taxpayers, it preserves credibility and helps avoid legal disputes with the Department of Revenue.
What documentation must accompany Schedule 1299-DA?
Attach copies of the other states’ filed tax returns, W-2s, or K-1s showing withholding and payments. Failure to attach proof can lead to denial of the credit. For convenience, you can track and upload copies directly through the MyTax Illinois portal.
K-12 education expense credit in IL?
Illinois offers a K-12 education expense credit (caps/eligibility apply). See the credits list in results.
Do unused credits carry forward to future years?
Most individual credits on Schedule ICR (Property Tax, Education Expense) apply only to the current tax year and cannot be carried forward. However, certain business-related credits listed on Schedule 1299-A can be carried forward or backward depending on statutory rules.
Saver’s Credit in IL?
The Saver’s Credit is federal; IL doesn’t usually add a separate state version.
Important Notes
All calculations are estimates for guidance only. Always review your return and consider professional advice when submitting official filings.