Property Tax

Property Tax in Illinois: Complete Guide 2026

Updated 2026-03-10

Data Notice: Figures, rates, and statistics cited in this article are based on the most recent available data at time of writing and may reflect projections or prior-year figures. Always verify current numbers with official sources before making financial, medical, or educational decisions.

Property Tax in Illinois: Complete Guide 2026

Tax information is for educational purposes only and does not constitute tax advice. Consult a licensed tax professional for your specific situation.

Illinois has the second-highest property tax rates in the nation, driven largely by heavy reliance on local property taxes to fund schools and a fragmented system of overlapping taxing districts. The state’s average effective rate of ~2.08% is more than double the national average, making property tax the single largest tax burden for most Illinois homeowners.

Illinois Property Tax Rates (2026)

MetricRate / Amount
Average effective rate~2.08%
National average effective rate~0.99%
Median home value~$240,000
Median annual property tax~$4,990

Illinois has no state-level property tax. All property taxes are assessed by county assessors and collected by county treasurers, with rates set by overlapping taxing districts — school districts, municipalities, counties, fire protection districts, park districts, library districts, and more. A single property may fall within 10 to 15 overlapping taxing districts.

Property Tax by Select County

CountyAvg. Effective RateMedian Tax Paid
Cook (Chicago)~1.95%~$4,800
Lake~2.65%~$8,200
DuPage~2.10%~$6,900
Will~2.50%~$6,100
Kane~2.55%~$6,200
McHenry~2.60%~$5,800
Winnebago (Rockford)~2.85%~$4,100
Sangamon (Springfield)~1.90%~$3,200

How Illinois Property Tax Works

Assessment Process

Illinois uses a triennial (every three years) reassessment cycle in Cook County and a four-year cycle in most other counties. Properties are assessed at 33.33% of fair market value (one-third), except in Cook County, which uses a classification system:

Property Class (Cook County)Assessment Level
Residential (Class 2)10% of market value
Commercial (Class 5a)25% of market value
Industrial (Class 5b)25% of market value

An equalization factor (multiplier) is applied by the Illinois Department of Revenue to bring Cook County assessments in line with the statutory one-third level. This multiplier changes annually and frequently increases effective tax burdens.

Tax Rate Determination

Tax rates are computed by dividing each taxing district’s levy by the total assessed value in the district. The Property Tax Extension Limitation Law (PTELL) — commonly called the “tax cap” — limits the annual increase in a taxing district’s extension (total levy) to 5% or the rate of CPI inflation, whichever is lower. However, new construction, annexations, and voter-approved referenda can allow increases beyond the cap.

Exemptions and Deductions

  • General Homestead Exemption: Reduces assessed value by $10,000 in Cook County and $6,000 in all other counties for owner-occupied primary residences.
  • Senior Homestead Exemption: Additional $8,000 reduction in assessed value for homeowners 65+ (available annually with application).
  • Senior Citizens Assessment Freeze (SCAF): Freezes the assessed value of the home at the base year level for homeowners 65+ with household income of ~$65,000 or less. This is one of Illinois’ most valuable exemptions for long-term senior homeowners.
  • Disabled Persons Homestead Exemption: $2,000 reduction in assessed value.
  • Disabled Veterans Standard Exemption: $2,500 to $5,000 reduction based on disability rating. Veterans rated 70%+ disabled may qualify for a full exemption.
  • Returning Veterans Exemption: $5,000 reduction in the year following return from active duty.
  • Home Improvement Exemption: Up to $75,000 of assessed value attributable to home improvements is exempt for four years after the improvement.

Comparison to National Average

MetricIllinoisNational Average
Average effective rate~2.08%~0.99%
Median annual tax paid~$4,990~$2,700
Assessment ratio33.33% (10% Cook residential)Varies
Tax cap5% or CPI (PTELL)Varies

Illinois’ effective rate is more than double the national average. Combined with a 4.95% flat income tax and sales taxes averaging ~8.83%, Illinois ranks among the highest overall tax burden states in the nation.

Tips for Minimizing Illinois Property Tax

  1. File for every exemption you qualify for. In Cook County, exemptions must be applied for annually (or renewed periodically). The homestead and senior exemptions combined can reduce your assessed value by $18,000 or more, translating to hundreds or thousands in savings.
  2. Appeal your assessment. Cook County allows online appeals through the Assessor’s Office and the Board of Review. Downstate counties offer appeals through the county Board of Review. Success rates are high, particularly when you provide comparable sales data.
  3. Apply for the Senior Assessment Freeze. If you are 65+ with household income under ~$65,000, the SCAF exemption can save you thousands as property values rise around you.
  4. Check the equalization multiplier. In Cook County, the state equalization factor can significantly inflate your tax bill. Understanding when the multiplier changes helps you anticipate and plan for higher bills.
  5. Monitor taxing district referenda. Bond referenda for schools, parks, and infrastructure directly increase your tax rate. Staying informed and participating in local elections is one of the few ways to control rates.
  6. Consider the home improvement exemption for renovations. If you plan renovations, this exemption shields up to $75,000 in added assessed value for four years.

Key Takeaways

  • Illinois’ average effective property tax rate of ~2.08% is the second highest in the nation
  • Overlapping taxing districts (often 10-15 per property) drive high total rates
  • Cook County uses a classification system with a state equalization multiplier that frequently increases effective burdens
  • The Senior Citizens Assessment Freeze is one of the most valuable property tax relief programs in any state
  • Annual appeals and exemption filings are critical to managing your tax bill
  • PTELL caps levy growth but does not prevent rate increases from declining assessed values in a district

Next Steps