Illinois Property Tax Calculator
2026Calculate property taxes in Illinois. The average effective property tax rate in IL is 2.07%, which is above the national average of 1.1%. Estimate your annual property tax bill.
Written and reviewed by Konstantin Iakovlev · Methodology · Updated
Annual Property Tax
$7,245.00
Monthly Equivalent
$603.75
Effective Rate
2.070%
Property Tax Breakdown
| Assessed Value | $350,000.00 |
| Homestead Exemption | $0.00 |
| Taxable Value | $350,000.00 |
| Annual Tax | $7,245.00 |
| Monthly Equivalent | $603.75 |
Disclaimer: This calculator is for informational purposes only and does not constitute tax, financial, or legal advice. Results are estimates based on the information you provide and current rates. Always consult a qualified tax professional or financial advisor for advice specific to your situation.
How is property tax calculated in Illinois?
Illinois's average effective property tax rate is 2.07% of assessed value (2026), placing it among the highest in the country. Property tax is administered by counties and municipalities — the state sets a framework, but local taxing authorities (school districts, county boards, special-service districts, fire/police districts) levy their own millage rates that stack onto the bill.
Your tax bill is the assessed value times the combined millage rate (1 mill = $1 per $1,000 of assessed value). Many jurisdictions assess at less than 100% of market value (e.g., 80% or 50%), so the effective rate on market value can be much lower than the headline millage. Common reductions include homestead exemptions (primary residence discount), senior or disabled-person freezes, veteran exemptions, and farm/agricultural use deferrals — these can cut a primary-residence bill by 10–50% in many states.
Most jurisdictions reassess property values every 1–4 years; rapid market gains can produce large bill jumps unless capped by state law (e.g., California's Proposition 13 limits annual increases to 2% on a primary residence; Texas caps homesteads at 10%/yr). Property tax is deductible federally as part of the SALT itemized deduction, capped at a combined $40,000 in 2026 under OBBBA (raised from $10,000), with a 30% phase-down on MAGI above $500,000 (floor $10,000). Use this calculator to estimate your annual bill and monthly escrow contribution.
Illinois relief programs: The general homestead exemption ($6,000–$10,000 depending on county), Senior Citizens Homestead Exemption (additional $5,000), Senior Citizens Assessment Freeze (income-tested), and Long-Time Occupant Exemption. Cook County has its own enhanced limits.
Illinois property assessment, homestead exemption, and appeal process
- Assessment ratio
- Cook County 10%, downstate counties 33⅓% of market value
- Median home price (Q4 2025)
- $285,000
- Homestead exemption
- General Homestead $6K assessed value reduction; senior exemption $5K additional; senior assessment freeze for under $65K income
Illinois has one of the highest effective property-tax rates in the country (~2.05%), driven by school-district funding through property taxes. Cook County uses a 10% assessment ratio (single-family residential) while downstate counties use 33⅓%. The General Homestead Exemption reduces assessed value by $6,000 ($10,000 in Cook County). Seniors 65+ get an additional $5,000 exemption plus an Assessment Freeze if income is under $65,000. Cook County reassessments are on a triennial cycle (City of Chicago, North Tri, South Tri).
Illinois Property Tax Details (2026)
| Avg. Effective Property Tax Rate | 2.07% |
| National Average | 1.1% |
| vs. National Average | +0.97% above |
| Estate Tax | Yes (exemption: $4,000,000) |
| State Sales Tax | 6.25% |
| State Income Tax | 4.95% (flat) |
Illinois property tax — frequently asked questions
Why is Illinois property tax so high?
Illinois has the 2nd-highest effective property tax rate in the country (~2.05%), driven by school-district funding through property taxes (rather than state income tax). Cook County uses 10% assessment ratio for single-family residential while downstate counties use 33⅓%. A typical $400K home in Chicago suburbs pays $8,000-$15,000/year in property tax. The General Homestead Exemption reduces assessed value by $6,000 ($10,000 in Cook County); seniors 65+ get an additional $5,000 + the Senior Citizens Assessment Freeze for under-$65K-income owners.
How does Cook County property tax assessment work?
Cook County uses a triennial reassessment cycle (one-third of properties each year): City of Chicago, North Tri (north suburbs), and South Tri (south suburbs). Assessments are based on market value × 10% Class 1 ratio. The Cook County Assessor publishes proposed values; appeals go through the Board of Review (typically 30-day window) and then the Property Tax Appeal Board (PTAB) for state-level appeal. Cook County's assessment volatility (large value swings between cycles) makes appealing common.
When are Illinois property tax bills due?
Illinois bills issued in two installments: Cook County's 1st installment is due in early March (typically around 55% of prior year's total); 2nd installment in early August (final reconciliation). Outside Cook County, most counties use semi-annual schedules tied to fiscal-year start. Delinquent taxes accrue 1.5% monthly interest. Tax sales (annual auctions of unpaid liens) start ~13 months after delinquency.
Does Illinois have a property tax freeze for seniors?
Yes. The Illinois Senior Citizens Assessment Freeze Homestead Exemption freezes the assessed value (not the tax bill — local rates can still rise) for owners 65+ with under $65,000 household income. Apply through your local assessor with proof of age + income. The freeze is renewable annually. Combined with the Standard Senior Homestead Exemption ($5K reduction), it provides meaningful relief for low-income seniors despite IL's high effective rate.