Illinois Tax Tables
Illinois Tax Tables provide a complete reference of how state income tax is calculated for each supported year. These tables summarise the official rules issued by the Illinois Department of Revenue and present them in a clear structure that matches the calculations used in our Illinois Tax Calculator. They are useful for checking withholdings, estimating liability, reviewing historical tax years and understanding how state policy shapes taxable income.
Quick Access Tools
Tax Years
Select a tax year to view the official Illinois tax rates and rules used in our calculators. Each page shows the brackets or flat tax rate, deduction amounts, credit structures, withholding guidance and any year-specific updates published by the Illinois Department of Revenue. You can also access the matching Illinois Tax Calculator for precise calculations for that year.
How Illinois Calculates Income Tax
Illinois uses a flat income tax rate applied to all taxable income. These rules determine how wages and other taxable income are assessed for Illinois returns, with updated tables released each year to reflect legislation and inflation changes. For a broader explanation of how tax tables work, see our Tax Tables guide.
Certain jurisdictions within Illinois also levy local or county income taxes. These appear in the annual state tax tables and may affect residents, part-year residents or nonresidents depending on local rules.
Illinois supports resident, nonresident and part-year filing rules. The tax tables help clarify which thresholds apply when income is earned both inside and outside the state.
What Is Contained in the Illinois Tax Tables?
Each tax-year page provides a structured summary of the components Illinois uses to calculate individual income tax. While details vary by year, the state tax tables generally include the following elements:
- Flat tax rate applied to taxable income.
- Standard deduction amounts for each filing status.
- Itemized deductions where permitted under Illinois law.
- Dependent and family-related credits including any child-based or filer-based reductions.
- State Earned Income Credit (EIC), including percentage match and income limits.
- Retirement income rules including partial or full exemptions for pensions or Social Security.
- State withholding tables used by employers for payroll calculations.
Together, these elements provide a transparent breakdown of how Illinois calculates tax for each year. This structure helps taxpayers review year-to-year changes, employers validate payroll withholding and financial planners analyse how Illinois’s rules differ from federal requirements. All values shown in our Illinois Tax Tables match the official figures published by the state.
Frequently Asked Questions
Mortgage vs take-home planning
Try the Mortgage Calculator and revisit this IL page.
Where do I mail the completed IL-1040-V and payment?
Mail the completed voucher and payment to the address printed on the voucher (Illinois Department of Revenue, Springfield IL 62726-0001) unless told otherwise during filing.
Do charitable gifts affect IL tax?
IL doesn’t mirror federal itemized deductions; charitable gifts matter federally, not typically for IL base.
Why don’t my payroll brackets match?
Employer systems use rounding/timing and supplemental methods; small variances are normal.
Does Illinois tax Social Security or pension income?
No. Illinois exempts most retirement income—including Social Security, pensions, and IRA withdrawals—from state income tax. These subtractions are reported on Schedule M.
Important Notes
All calculations are estimates for guidance only. Always review your return and consider professional advice when submitting official filings.