When Do Property Tax Bills Come Out in Illinois? Key Dates and Deadlines

When Do Property Tax Bills Come Out in Illinois? Key Dates and Deadlines

Illinois property taxes are complicated by the fact that Cook County (Chicago) operates under a different system than the rest of the state. We cover when Do Property Tax Bills Come Out in Illinois? Key Dates and Deadlines from start to finish here.

If your deadline has already passed, check whether your state has a secondary appeal window. Some states allow filing with a higher court or board after the initial deadline. If no secondary option exists, start preparing now for next year's appeal so you are ready the moment your next notice arrives.

Illinois Property Tax Calendar

When	What Happens	Your Action
January 1	Assessment date	Exemption qualification date
Varies by township	Assessment notices mailed	Review immediately
30 days after publication	Appeal deadline	File with Assessor or Board of Review
Spring (varies)	First installment tax bill	Pay (typically 55% of prior year's bill)
Summer-Fall (varies)	Second installment tax bill	Pay remaining balance

Deadlines in property tax are not flexible. Miss the filing window by even one day and you lose your right to appeal for the entire year. That is another 12 months of overpaying with no recourse. As soon as you receive your assessment notice, find the deadline and mark it on your calendar with a reminder set for two weeks before.

If your deadline has already passed, check whether your state has a secondary appeal window. Some states allow filing with a higher court or board after the initial deadline. If no secondary option exists, start preparing now for next year's appeal so you are ready the moment your next notice arrives.

Cook County vs. Rest of Illinois

Illinois property taxes are complicated by the fact that Cook County (Chicago) operates under a different system than the rest of the state.

Cook County

Cook County reassesses on a triennial (3-year) cycle. Different townships are reassessed in different years. The process includes:

1. Assessor's reassessment: New values published by township. You have 30 days to appeal to the Assessor's office.
2. Board of Review: After the Assessor's review period, the Board of Review opens its own appeal window (typically 30 days). This is a second chance if the Assessor did not reduce your value.

Cook County uses different assessment levels for different property types:

• Residential: 10% of market value
• Commercial: 25% of market value
• Industrial: 25% of market value

To find the implied market value of your Cook County home, multiply the assessed value by 10.

Full Cook County appeal guide

Rest of Illinois

Outside Cook County, properties are assessed at 33.33% of market value. Assessment notices are published in the local newspaper, and you have 30 days from publication to file with the county Board of Review.

Some counties outside Cook County also have a triennial cycle, while others assess annually. Check with your county assessor.

When Tax Bills Arrive

Illinois tax bills are notoriously late and unpredictable in timing, especially in Cook County:

• First installment: Usually mailed in January-March. It is 55% of the prior year's total tax bill. Due about 30 days after mailing.
• Second installment: Usually mailed in the summer or fall. This reflects the final tax calculation with updated assessments and rates. Due about 30 days after mailing.

Cook County second installment bills have been notoriously delayed in some years, sometimes arriving in October or November instead of the typical July-August window.

Deadlines in property tax are not flexible. Miss the filing window by even one day and you lose your right to appeal for the entire year. That is another 12 months of overpaying with no recourse. As soon as you receive your assessment notice, find the deadline and mark it on your calendar with a reminder set for two weeks before.

If your deadline has already passed, check whether your state has a secondary appeal window. Some states allow filing with a higher court or board after the initial deadline. If no secondary option exists, start preparing now for next year's appeal so you are ready the moment your next notice arrives.

Illinois Exemptions

Illinois offers several valuable exemptions:

Exemption	Reduction	Eligibility
General Homestead	Up to $10,000 off EAV ($10,000 in Cook County)	Owner-occupied primary residence
Senior Homestead	Up to $8,000 off EAV	Age 65+, owner-occupied
Senior Freeze	Freezes EAV at base year level	Age 65+, income under limit
Disabled Persons	$2,000 off EAV	Homeowners with qualifying disability
Disabled Veterans	Up to $100,000 off EAV	Veterans with service-connected disability

EAV = Equalized Assessed Value. These exemptions must be applied for and may need annual renewal. Full Illinois exemptions guide.

Do not assume you are automatically enrolled. Most exemptions require an application, and many homeowners lose years of savings simply because they never filed. Contact your county assessor's office or check their website for the application form. Bring proof of eligibility (age verification, disability documentation, veteran status, etc.) and file well before the deadline.

If you qualify for multiple exemptions, apply for all of them. In most jurisdictions, exemptions stack. A senior homeowner who is also a veteran can often claim both exemptions simultaneously, doubling the savings.

How to Appeal in Illinois

Cook County Process

1. File with the Cook County Assessor during the township's open appeal window (30 days after reassessment values are published)
2. If unsuccessful, file with the Cook County Board of Review during their open window
3. If unsuccessful, appeal to the Illinois Property Tax Appeal Board (PTAB) or Circuit Court

Outside Cook County

1. File with the county Board of Review within 30 days of assessment publication
2. If unsuccessful, appeal to PTAB or Circuit Court

The appeal process is designed to be accessible to regular homeowners, not just attorneys and tax professionals. You do not need to hire anyone to file. The key is preparation. Gather your evidence before the hearing, organize it clearly, and practice presenting your case in under 10 minutes. Lead with comparable sales, then cover any property record errors, and finish with photos or documentation of condition issues.

Keep your tone professional and factual. Review boards respond to evidence, not complaints. If you walk in with 3 strong comparable sales and a calm, organized presentation, you are already ahead of most appellants.

Your Next Steps

Here is what to do right now:

• Check your state's deadline. Use the tables above to find your state's specific dates. If your deadline is within the next 60 days, start preparing immediately.
• Open your assessment notice. If you received one recently, read it today. Do not set it aside. Check the assessed value, property details, and the appeal deadline printed on it.
• Gather comparable sales. If your assessed value looks too high, pull 3 to 5 recent sales of similar homes in your area. This is the single most important piece of evidence for any appeal.
• File for exemptions you have not claimed. Many homeowners miss exemptions simply because they never applied. Check what is available in your state and file before the deadline passes.

Frequently Asked Questions

Why are Illinois property taxes so high?

Illinois has one of the highest effective property tax rates in the nation (averaging over 2.0%). This is driven by heavy reliance on property taxes for school funding and the state's large number of overlapping taxing districts. Some areas have over a dozen taxing bodies stacking their rates.

When is my township's reassessment year (Cook County)?

Cook County rotates reassessments: City of Chicago, North/Northwest suburbs, and South/Southwest suburbs each on a 3-year cycle. Check the Cook County Assessor's website for your township's schedule.

What is the equalization factor (multiplier)?

The Illinois Department of Revenue applies an equalization factor (or "multiplier") to Cook County assessments to bring them in line with the state's 33.33% standard. The multiplier changes annually. When calculating your tax, the assessed value is multiplied by this factor before tax rates are applied.

Understanding this topic fully means looking at both the big picture and the specific details that apply to your situation. Every property is different, and the strategies that save the most money are the ones tailored to your particular home, location, and circumstances.

Start by gathering the basic facts about your property: its assessed value, the tax rate in your jurisdiction, and any exemptions currently applied. Then compare your situation to what is available. You may find opportunities for savings that you did not know existed.