Standard vs. Itemized Deductions in Illinois (2026)
Federal Standard Deduction
For 2024, the federal standard deduction is $14,600 for single filers and $29,200 for married filing jointly. About 90% of taxpayers take the standard deduction. It is automatic — no receipts or documentation required.
Illinois Deduction Rules
Illinois uses a flat 4.95% flat income tax rate starting from federal adjusted gross income. Most flat-rate states has its own standard deduction. Check the Illinois Department of Revenue for current IL standard deduction amounts, which differ from the federal amounts.
When Itemizing Makes Sense for Illinois Residents
- Mortgage interest on primary/secondary home exceeds standard deduction threshold when combined with other deductions
- High state and local taxes (capped at $10,000 SALT) — Illinois residents can include state income taxes + property taxes up to the $10,000 cap
- Significant charitable contributions (cash, non-cash, appreciated stock)
- Large unreimbursed medical expenses exceeding 7.5% of AGI
- Casualty or theft losses from federally declared disasters
Illinois Income Context
At Illinois's median household income of $72,205, most residents benefit more from the standard deduction than itemizing. Homeowners with large mortgages and significant IL income and property taxes are the most likely candidates for itemizing.
Frequently Asked Questions
Should I take the standard deduction or itemize in Illinois?
Take the standard deduction ($14,600 single / $29,200 joint in 2024) if your total itemized deductions are less. Itemize if you have large mortgage interest, significant charitable donations, or other deductible expenses that exceed the standard deduction. Illinois residents who pay significant state income tax (up to 4.95% flat) and property taxes may benefit from itemizing if combined deductions exceed $10,000 SALT cap + other items.
Does Illinois have its own standard deduction?
Yes, Illinois has its own state standard deduction amounts, which differ from the federal amounts. The state standard deduction is applied against Illinois taxable income separately from the federal calculation. Check the Illinois Department of Revenue for current state standard deduction amounts.
How does the $10,000 SALT cap affect Illinois residents?
Illinois residents who itemize can deduct state and local taxes up to $10,000. This includes IL income taxes + property taxes combined. For high earners paying 4.95% flat state income tax, the $10,000 cap can be reached quickly, limiting the benefit of the SALT deduction.
Is this standard vs. itemized calculator free for Illinois residents?
Yes, 100% free with no signup. Enter your deductible expenses — mortgage interest, state and local taxes, charitable donations, and medical expenses — and the calculator will show whether itemizing saves you more than the standard deduction for your Illinois filing situation.