Market value
The county assessor estimates what your home is worth. In Cook County, residential property is generally assessed at 10% of market value; most other Illinois counties assess at one-third.
Chicago & Illinois property tax guide
Understand the tax bill before you buy.
Illinois property taxes are among the highest in the country—and they vary street by street. Here is how they are calculated, how counties differ, and how to compare the true monthly cost of a home.
From value to bill
How an Illinois tax bill is built.
Every bill follows the same path: market value, assessed value, equalization, exemptions, then the local rate. Understanding the steps tells you where a bill can move—and where you can push back.
Assessed value
The assessment percentage is applied to market value to produce the assessed value—the number your tax bill is actually built on.
Equalization
The state applies an equalization factor (multiplier) to bring assessments to a uniform level across counties. Cook County's multiplier changes each year.
Exemptions
Homeowner, senior, and other exemptions reduce the equalized assessed value. The homeowner exemption alone can meaningfully lower a bill on a primary residence.
Local tax rate
Schools, municipalities, parks, libraries, and other taxing bodies each set levies. The combined rate is applied to your equalized assessed value to produce the bill.
General orientation only. Assessment practices, multipliers, and deadlines change—verify current figures with the county before relying on them.
County by county
The same price can mean very different bills.
Where a home sits determines which system assesses it, which bodies tax it, and how the bill behaves over time.
Cook County (Chicago & near suburbs)
Bills arrive in two installments and are paid a year in arrears—you are paying last year's taxes. Reassessments happen on a three-year cycle, and recent reassessments have shifted bills significantly in some neighborhoods.
Lake County (North Shore)
Also pays in arrears with two installments, but assessments follow different township schedules. North Shore communities often carry higher absolute tax bills because home values and school levies are higher.
DuPage & collar counties (Western / Southwest suburbs)
Assessed at one-third of market value with no Cook-style classification system. Rates vary widely by school district and municipality, so two similar homes in neighboring towns can have very different bills.
Beyond the list price
Put taxes into the monthly comparison.
Two homes at the same price can differ by hundreds of dollars a month once taxes are escrowed. We compare the real numbers before you commit.
01
Mortgage
02
Property taxes
03
Insurance
04
Association fees
05
Special assessments
Estimates vary by property and lender. Confirm all figures during due diligence.
Before you offer
Tax checks worth doing on every home.
- Pull the actual most recent tax bill
- Check for expiring or missing exemptions
- Ask about reassessment timing in that township
- Compare bills on similar nearby homes
- Estimate the escrow impact on your payment
- Consider an appeal if the assessment looks high
Personalized review
Want the real numbers on a specific home?
Send us an address or a community you're considering. We'll pull the actual tax history and walk through what it means for your monthly cost.
Primary contact for Chicago & Illinois
Rosemary Del Cid
Kap Rate Living & Kap Rate Group
Rosemary will learn what you need and connect you with the right local agent for this area.
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