You Got Your Cook County Property Tax Assessment - Now What?
Thousands of Cook County homeowners get their assessment notices and feel overwhelmed. Here's your step-by-step guide to what happens next.
Understanding Your Assessment Notice
What the Numbers Actually Mean
Assessed Value vs. Market Value
Your assessment notice shows an assessed value, not your property's market value. In Cook County:
- Residential properties: Assessed at 10% of estimated market value
- Commercial/Industrial properties: Assessed at 25% of estimated market value
Example: If your home's market value is $400,000, your assessed value should be around $40,000 (10% of $400,000).
Why Cook County Assessments Change
Cook County uses a triennial reassessment cycle, meaning your property is reassessed every 3 years. The county is divided into three districts:
North District
Reassessed in: 2019, 2022, 2025, 2028...
South District
Reassessed in: 2017, 2020, 2023, 2026...
City District
Reassessed in: 2018, 2021, 2024, 2027...
Your assessment can change significantly during these reassessment years, especially if property values in your area have increased.
The Key Dates You Cannot Miss
- ⚠️Assessment Notice Date: The date your notice was mailed (check the notice)
- ⚠️Assessor Appeal Deadline: 30 days from the date your notice was mailed
- ⚠️Board of Review Deadline: Typically 30 days after the Assessor completes their review (check the Board of Review website for exact dates)
Missing these deadlines means you cannot appeal for that tax year. Mark your calendar immediately!
Should You Appeal?
Quick Test: Is Your Assessed Value Higher Than Comparable Homes?
The simplest way to determine if you should appeal is to compare your assessment to similar properties in your area. Here's how:
- Find 3-5 properties similar to yours (same size, age, condition, location)
- Look up their assessed values on the Cook County Assessor's website
- Calculate the assessment per square foot for each property
- Compare: If your assessment per square foot is significantly higher, you may have a case
Red Flags That Suggest You're Overassessed
- ✗Your assessed value increased dramatically in a reassessment year
- ✗Nearby similar homes sold for less than your assessed value suggests they're worth
- ✗Your property has issues (foundation problems, outdated systems, etc.) that weren't considered
- ✗Your assessment per square foot is higher than comparable properties
- ✗You recently purchased the property for less than the assessed value suggests
How to Look Up Your Neighbors' Assessments Online
The Cook County Assessor's website makes it easy to research comparable properties:
- Visit cookcountyassessor.com
- Use the property search tool to find properties by address or PIN
- View the property details, including assessed value, square footage, and property characteristics
- Compare multiple properties to find patterns
Tip: Look for properties within a half-mile radius with similar square footage, age, and property type for the best comparison.
Your Three Options
Option 1: Do Nothing
Accept your assessment and pay the taxes as calculated.
When this is OK:
- Your assessment is fair compared to similar properties
- You've verified your assessment is accurate
- The potential savings don't justify the time investment
Option 2: Appeal It Yourself
File an appeal with the Cook County Assessor's office and handle the process yourself.
Best for:
- Simple overassessment cases
- When you have time to research and attend hearings
- Properties with clear comparable sales data
Option 3: Hire Professional Help
Work with a property tax consultant or attorney to handle your appeal.
Best for:
- Complex cases or commercial properties
- When you don't have time to research
- High-value properties with significant potential savings
The Cook County Appeal Timeline
Assessor's Office Appeal (First Level)
This is your first opportunity to appeal. You must file within 30 days of receiving your assessment notice.
Timeline: File within 30 days → Decision typically within 30-60 days
Many cases are resolved at this level, but if you're not satisfied, you can proceed to the Board of Review.
Board of Review Appeal (Second Level)
If the Assessor doesn't reduce your assessment enough (or denies it), you can appeal to the Board of Review.
Timeline: File within 30 days after Assessor's decision → Hearing scheduled → Decision can take several months
This is a more formal process that may require attending a hearing and presenting evidence to a 3-person board.
Why Timing is Critical
Missing a deadline means you cannot appeal for that tax year. You'll have to wait until the next reassessment cycle (3 years later) to appeal again.
- ✓Set calendar reminders as soon as you receive your assessment notice
- ✓Start gathering evidence immediately—don't wait until the deadline
- ✓File your appeal early to avoid last-minute issues
What You'll Need to Appeal
Recent Comparable Sales in Your Area
The strongest evidence for an appeal is recent sales of similar properties in your area. Look for:
- Properties sold within the last 12-18 months
- Similar square footage (within 10-15%)
- Similar age and condition
- Within a half-mile radius
- Same property type (single-family, condo, etc.)
Where to find: Cook County Assessor's website, Zillow, Redfin, or real estate databases
Photos of Any Property Issues
If your property has issues that reduce its value, document them:
- Foundation problems or cracks
- Outdated systems (HVAC, plumbing, electrical)
- Water damage or mold
- Structural issues
- Neighborhood issues (proximity to highways, commercial properties, etc.)
Evidence of Assessment Errors
Check your property record for inaccuracies:
- Incorrect square footage
- Wrong number of bedrooms or bathrooms
- Incorrect property characteristics (basement finish, garage size, etc.)
- Comparable properties with lower assessments
How to Gather This Information
Option 1: Do it yourself - Research comparable sales, take photos, and compile evidence manually. This can take 10-20 hours.
Option 2: Use Property Tax Hand - Our system automatically finds comparable sales, analyzes your property, and generates a professional report with all the evidence you need in minutes.
Not Sure If You Should Appeal?
Our free property analysis tool can help you determine if you're overassessed in under 5 minutes.
Analyze My Property Now →This information is provided for educational purposes. For the most current information about Cook County's appeal process, visit the Cook County Assessor's Office or the Cook County Board of Review.