Skip to content
Free check
Free check

Independent. Not affiliated with any government agency.

Illinois · County guide

Cook County property tax appeal

A Cook County property tax appeal can be filed at two local stages each year: first the Cook County Assessor, then the Board of Review. Filing is free at both. Each township has its own dates, and the Assessor's window stays open at least 30 business days after its notices go out.

This season

Next deadline
Oct 8, 2026
5 days left
Hyde Park Township · Cook County Assessor's Office

Opens Aug 26, 2026Closes Oct 8, 2026

Source: Assessment & Appeal Calendar (page last updated 9/22/26) - Cook County Assessor's OfficeLast checked

Check a Cook County home for free

Enter the address or parcel number from your notice. We compare the assessment with similar homes and show the numbers, whatever they are. You decide and file yourself.

Excellent5.0 out of 5 · Based on reviewsRead reviews →

Reduced my assessment by $112,000!

I couldn’t believe the difference. My property assessment was reduced by $112,000. I’m extremely happy with the outcome!

Spencer CaldwellHomeowner

A $106,300 reduction

We had no idea there was this much room between our original assessment and the final number. Very happy with the outcome.

Megan HollisHomeowner
Where to file
Assessor: online (SmartFile). Board of Review: online portal or in person.
Fee
None at either stage
Office address
118 N. Clark Street, Room 320, Chicago, IL 60602 · 312-443-7550
Our coverage
Free check available
  • Independent guide — not affiliated with Cook County or any government agency.
Last updated
September 30, 2026
Sources last checked
October 3, 2026
Status
Verified guide

How we verify facts

When and where do I file a Cook County property tax appeal?

Who hears a Cook County appeal?

The stages in order. We are not affiliated with any of these offices.

  1. 1

    Cook County Assessor's Office

    Filing: appeal

    5 days left
  2. 2

    Cook County Board of Review

    Filing: complaint

  3. 3

    Circuit Court of Cook County (tax objection)

    Filing: objection

  4. 4

    Illinois Property Tax Appeal Board

    Filing: appeal

Where is the Cook County office?

Cook County Assessor's Office[6]

Downtown Office

Address
118 N. Clark Street, Room 320, Chicago, IL 60602
Hours
8:30 a.m. - 5:00 p.m.
Email
assessor.onlineappeals@cookcountyil.gov (appeal system issues)

Cook County Board of Review[49]

Address
118 N. Clark Street, Room 601, Chicago, IL 60602
Hours
Monday-Friday, 9 AM - 5 PM

Illinois Property Tax Appeal Board[18]

Hours
Monday-Friday 8:30-5:00

We are not affiliated with this office. Hours can change, so call before you visit.

Which Cook County filing windows are coming up?

Cook County filing windows
ClosesAreaWho hears itStatus
Oct 8, 2026Hyde Park TownshipCook County Assessor's Office · Official source · Last checked Sep 29, 20265 days left
Oct 14, 2026Leyden TownshipCook County Assessor's Office · Official source · Last checked Sep 29, 202611 days left
Oct 15, 2026Worth TownshipCook County Assessor's Office · Official source · Last checked Sep 29, 202612 days left
Oct 22, 2026Wheeling TownshipCook County Assessor's Office · Official source · Last checked Sep 29, 2026Open now
Oct 27, 2026Proviso TownshipCook County Assessor's Office · Official source · Last checked Sep 29, 2026Open now
Oct 29, 2026Lake TownshipCook County Assessor's Office · Official source · Last checked Sep 29, 2026Open now
Nov 4, 2026Palatine TownshipCook County Assessor's Office · Official source · Last checked Sep 29, 2026Open now
Nov 6, 2026Orland TownshipCook County Assessor's Office · Official source · Last checked Sep 29, 2026Open now

Showing the 8 soonest of 51. Every township is listed below.

When were past Cook County deadlines?

Past Cook County filing windows
Tax yearWindowOffice
2026Closed October 2, 2026Calumet · Cook County Assessor's Office
2026Closed September 29, 2026Lemont · Cook County Assessor's Office
2026Closed September 29, 2026Berwyn · Cook County Board of Review
2026Closed September 29, 2026Cicero · Cook County Board of Review
2026Closed September 29, 2026Elk Grove · Cook County Board of Review
2026Closed September 29, 2026Lake View · Cook County Board of Review
2026Closed September 29, 2026Maine · Cook County Board of Review
2026Closed September 29, 2026Palos · Cook County Board of Review

When is the Cook County appeal deadline?

Each of Cook County's 38 townships has its own appeal window. The Assessor opens a township when it mails that township's assessment notices; the last day to file is printed on the notice. The Board of Review opens townships in groups after the Assessor finishes them.

See all Cook County appeal deadlines for 2026

How do I appeal my Cook County assessment?

  1. Find your township's window on your assessment notice or the Assessor's calendar.

  2. Look up your home's details on the Assessor's site by PIN or address, and check them against your notice.

  3. Gather evidence. Common grounds are that your home is assessed out of line with similar homes, that the value is too high, or that the county's details about your home are wrong.

  4. If you use comparable homes at the Assessor, include at least 3; the Assessor recommends 5, from your assessment neighborhood.

  5. State the market value you believe is correct, and disclose a purchase in the two years before January 1 of the appeal year.

  6. File online with the Assessor's SmartFile system by the closing date, with all your evidence. Late appeals and late evidence are not accepted.

  7. When the Board of Review opens your township, you can file there too, whether or not you appealed to the Assessor.

What happens after the Board of Review?

You may appeal further to the state Property Tax Appeal Board (PTAB) within 30 days of the Board's decision notice (in Cook, or 30 days after the Board closes the township, if later), or file a tax objection in Circuit Court after paying your taxes. Choosing PTAB rules out a valuation tax objection in court for that year.

When is the deadline to appeal a property tax assessment in Cook County?

The soonest deadline we list: Hyde Park, Cook County Assessor's Office — Closes October 8, 2026. Cook County Assessor's Office: Assessor appeals stay open at least 30 business days after the township's notices go out. The exact last day is posted on the Assessor's calendar and printed on the notice.

Deadline ruleCook County Assessor's Office
Assessor appeals stay open at least 30 business days after the township's notices go out. The exact last day is posted on the Assessor's calendar and printed on the notice.[1]
Deadline ruleCook County Board of Review
The Board of Review opens townships in groups after the Assessor finishes them; each group stays open at least 30 days. The Board posts the exact dates.[2]
Deadline ruleIllinois Property Tax Appeal Board
Appeal to the Property Tax Appeal Board within 30 days of the Board of Review decision notice (in Cook, or 30 days after the Board closes the township, whichever is later).[3]
When a filing counts as on timeCook County Assessor's Office
The appeal and all evidence must be filed by the township closing date.[4]
When a filing counts as on timeCook County Board of Review
Online complaints must be in by the closing date; mailed complaints count as filed on the U.S. Postal Service postmark date.[5]
Holidays that pause business-day counts
Cook County Assessor office holidays in 2026 (used to count business days): 13 dates, including Columbus Day (Oct 12), Veterans Day (Nov 11) and Thanksgiving (Nov 26).[6]
Deadline detailFirst-installment due date
The Tax Year 2025 first-installment Cook County property tax bill was due Wednesday, April 1, 2026.[7] (latest published: tax year 2025)
Deadline detailSecond-installment due date
The Tax Year 2025 second-installment Cook County property tax bill is due Thursday, October 1, 2026.[7] (latest published: tax year 2025)
Deadline detailTax bill schedule
The first installment is 55% of the previous year's total bill. The second installment can't be calculated until the Board of Review finishes every appeal in all 38 townships.[2]
Deadline detailTax bill schedule
Tax Year 2025 second-installment bills were mailed by the Treasurer on September 1, 2026 and are due October 1, 2026.[8] (latest published: tax year 2025)
Deadline detailCook County Assessor's Office · Hard deadline
Late appeals or late evidence are not accepted, except when the Assessor's own system failed.[4]
Deadline detailCook County Assessor's Office · Date printed on your notice
The last day to file is printed on each reassessment notice.[9]
Deadline detailCook County Board of Review · When evidence is due
Evidence can be filed until the Board's evidence deadline for the group (after the filing window closes).[5]
Deadline detailCook County Board of Review · Statutory minimum
By law, taxpayers get at least 20 days after the Board publishes a township's filing notice.[10]
Deadline detailIllinois Property Tax Appeal Board · Board response
After the PTAB notifies the Board of Review of the appeal, the Board has 90 days to file its Notes on Appeal and evidence.[11]
Deadline detailIllinois Property Tax Appeal Board · When evidence is due
Evidence goes in with the PTAB petition. If it isn't ready, ask for an extension in writing with the petition; the PTAB grants 30 days.[3]
Deadline detailIllinois Property Tax Appeal Board · Rebuttal
Each party has 30 days after first receiving the other side's evidence to file rebuttal evidence at the PTAB.[12]

Who decides a property tax appeal in Cook County?

Cook County has two local appeal steps (Assessor, then Board of Review). After the Board of Review, an owner may go to the state Property Tax Appeal Board or to Circuit Court. Chicago homes are appealed at the Cook County Assessor (the Chicago townships are on the Assessor's appeal calendar) and then the Cook County Board of Review.

Appeal steps
Cook County has two local appeal steps (Assessor, then Board of Review). After the Board of Review, an owner may go to the state Property Tax Appeal Board or to Circuit Court.[2]
Appeal stepsChicago
Chicago homes are appealed at the Cook County Assessor (the Chicago townships are on the Assessor's appeal calendar) and then the Cook County Board of Review.[13]
Appeal stepsCook County Assessor's Office · Next step
If you disagree with the Assessor's decision, you can appeal to the Cook County Board of Review.[4]
Appeal stepsCook County Board of Review · Next step
After the Board of Review, you may appeal further to the Property Tax Appeal Board (PTAB) or the Cook County Circuit Court.[2]
Appeal stepsCook County Board of Review · Prerequisite
You can appeal to the Board of Review whether or not you appealed to the Assessor; the Board is not bound by the Assessor's decision.[2]
Appeal stepsIllinois Property Tax Appeal Board · Exclusive
Choosing PTAB rules out a valuation tax objection in Circuit Court for that year (and vice versa).[14]
Appeal stepsCircuit Court of Cook County (tax objection) · Prerequisite
A court tax objection on assessment is only allowed if the Board of Review remedy was used first.[15]
What the appeal is calledChicago townships
The City of Chicago is made up of 8 assessment townships: Rogers Park, West Chicago, Jefferson, North Chicago, South Chicago, Lake, Lake View and Hyde Park.[16]
What the appeal is calledCook County Assessor's Office
At the Assessor this is called an "appeal", filed online through SmartFile.[4]
What the appeal is calledCook County Board of Review
At the Board of Review the filing is formally a "complaint" (the Board also calls it an appeal).[5]
What the appeal is calledCook County Board of Review · Reviewed value
The Board of Review reviews the assessment the Assessor set (certified) for your township, called here the Assessor-certified value.[2]
What the appeal is calledCircuit Court of Cook County (tax objection)
The court route is a "tax objection complaint", filed after paying the taxes.[15]
What the appeal is calledIllinois Property Tax Appeal Board
At the state Property Tax Appeal Board (PTAB) you file a petition to appeal the Board of Review decision.[14]
Tax objection in circuit courtCircuit Court of Cook County (tax objection)
Tax objection complaints in Cook are due within 165 days after the first penalty date of the final (second) installment, after paying the taxes.[15]

How do I file a property tax appeal in Cook County?

Cook County Assessor's Office: File online with the Assessor's SmartFile system. Cook County Assessor's Office · Filing without a lawyer: Owners filing for themselves who cannot use SmartFile may email the appeal or file in person at 118 N. Clark St., Room 320.

How to fileCook County Assessor's Office
File online with the Assessor's SmartFile system.[4]
How to fileCook County Assessor's Office · Filing without a lawyer
Owners filing for themselves who cannot use SmartFile may email the appeal or file in person at 118 N. Clark St., Room 320.[4]
How to fileCook County Board of Review
File online through the Board of Review portal, or in person at 118 N. Clark St., Room 601.[5]
How to fileCook County Board of Review · In person
In-person filing: Board of Review office, Room 601, 118 N. Clark St., Chicago.[5]
How to fileCook County Board of Review · Pre-filing
Owners can pre-file a Board of Review appeal before their township opens.[17]
How to fileIllinois Property Tax Appeal Board
PTAB petitions can be filed online (eFiling Portal), by mail, or in person. Fax is not accepted.[3]
How to fileIllinois Property Tax Appeal Board · Fax
The PTAB does not accept petitions or evidence by fax.[18]
How to fileIllinois Property Tax Appeal Board · Paper
Paper PTAB appeals must be mailed or hand-delivered to the Springfield office; the PTAB recommends e-filing all appeals.[19]
FormsCook County Assessor's Office
Assessor appeal forms are on the Assessor's forms page; online filing is preferred.[4]
FormsCook County Board of Review
Complaints must use the Board's official complaint form (the online filing uses it too).[5]
FormsCook County Board of Review · Complaint
The 2026 paper form is titled "2026 Real Estate Assessed Valuation Complaint".[20]
FormsIllinois Property Tax Appeal Board
PTAB appeals use the Board's prescribed petition form (for homes, the Residential Appeal Form), one petition per separately assessed parcel, identified by PIN.[3]
FormsIllinois Property Tax Appeal Board · Attachments
File one copy each of the PTAB petition, the Board of Review decision notice, and your evidence (three copies if over 500 pages).[3]
FormsIllinois Property Tax Appeal Board · Incomplete
The PTAB returns incomplete petitions (e.g. unsigned, or missing the assessed values or an e-mail address); the corrected petition is due within 30 days or the appeal is dismissed.[3]
Filing feeCook County Assessor's Office
There is no fee to appeal to the Assessor.[9]
Filing feeCook County Board of Review
There is no fee to file with the Board of Review.[2]
Filing feeIllinois Property Tax Appeal Board
There is no fee to appeal to the PTAB.[18]
Who may fileCook County Assessor's Office
No attorney is required to appeal to the Assessor, including for LLCs.[4]
Who may fileCook County Assessor's Office · Authorizing someone else
Anyone filing for an owner must file the Assessor's Authorization Form.[4]
Who may fileCook County Board of Review
Only the owner (for property in their own name) or an Illinois attorney may appear at the Board of Review.[5]
Who may fileCook County Board of Review · Consultants
Tax consultants may not represent a homeowner at the Board of Review.[21]
Who may fileCook County Board of Review · Companies and trusts
Companies, LLCs, condo associations and other entities must be represented by an attorney.[5]
Who may fileIllinois Property Tax Appeal Board
At PTAB hearings only Illinois-licensed attorneys may represent someone else; owners may represent themselves.[22]
Who may fileIllinois Property Tax Appeal Board · Companies and trusts
Corporations, LLCs, partnerships and similar entities must use an Illinois attorney at every stage.[22]
Informal reviewCook County Assessor's Office
The Assessor does not re-review its appeal decisions; the next step is the Board of Review.[4]
Informal reviewCook County Board of Review
After a decision you may ask the Board for a "Re-Review" within 3 days of the decision letter; new arguments are not allowed.[5]
HearingsCook County Board of Review
Board of Review hearings are held by phone for owners (attorneys by Microsoft Teams).[2]
HearingsCook County Board of Review · Notice
If you asked for a hearing when you filed, the Board mails you a hearing notice with the date and time; hearings are scheduled after your township closes.[23]
HearingsCook County Board of Review · Optional
A hearing is optional; owners can waive it without penalty.[23]
HearingsCook County Board of Review · Phone instructions
For a phone hearing, the Board's Clerk's office contacts you with instructions for joining by phone.[2]
HearingsIllinois Property Tax Appeal Board
PTAB hearings are held in Springfield or Des Plaines, elsewhere in Illinois, or by video conference.[24]
HearingsIllinois Property Tax Appeal Board · Notice
If the PTAB holds a hearing, it sends notice at least 20 days ahead. A video hearing needs the agreement of the Board and all parties.[24]
HearingsIllinois Property Tax Appeal Board · On record
PTAB may decide on the written record without a hearing; any party can request a hearing in writing.[24]

Upcoming appeal deadlines in every county we track

What applies to my township?

Each township has its own page with its dates and local figures. Your township is printed on your assessment notice.

Chicago homes: every Chicago township on one page in our Chicago property tax appeal guide.

  • BarringtonForecastExpected Aug 8, 2027 – Sep 23, 2027 · Cook County Assessor's OfficeMedian home assessment $77,000
  • BerwynForecastExpected May 24, 2027 – Jul 6, 2027 · Cook County Assessor's OfficeMedian home assessment $25,000
  • BloomForecastExpected Dec 9, 2026 – Jan 14, 2027 · Cook County Assessor's OfficeMedian home assessment $14,168
  • BremenForecastExpected Sep 24, 2027 – Oct 2, 2027 · Cook County Assessor's OfficeMedian home assessment $19,353
  • CalumetForecastExpected May 1, 2027 – Oct 2, 2027 · Cook County Assessor's OfficeMedian home assessment $13,000
  • CiceroForecastExpected May 17, 2027 – Jul 31, 2027 · Cook County Assessor's OfficeMedian home assessment $22,000
  • Elk GroveForecastExpected Jun 18, 2027 – Sep 1, 2027 · Cook County Assessor's OfficeMedian home assessment $40,000
  • EvanstonForecastExpected May 21, 2027 – Sep 9, 2027 · Cook County Assessor's OfficeMedian home assessment $61,000
  • HanoverForecastExpected Dec 23, 2026 – Jan 28, 2027 · Cook County Assessor's OfficeMedian home assessment $31,000
  • Hyde ParkOpenOct 8, 2026 · Cook County Assessor's OfficeMedian home assessment $13,701
  • JeffersonOpenNov 12, 2026 · Cook County Assessor's OfficeMedian home assessment $38,977
  • LakeOpenOct 29, 2026 · Cook County Assessor's OfficeMedian home assessment $19,861
  • Lake ViewForecastExpected Jul 13, 2027 – Dec 23, 2027 · Cook County Assessor's OfficeMedian home assessment $89,642
  • LemontForecastExpected Jun 9, 2027 – Sep 29, 2027 · Cook County Assessor's OfficeMedian home assessment $47,001
  • LeydenOpenOct 14, 2026 · Cook County Assessor's OfficeMedian home assessment $30,000
  • LyonsForecastExpected Sep 3, 2027 – Nov 27, 2027 · Cook County Assessor's OfficeMedian home assessment $33,000
  • MaineForecastExpected Jul 18, 2027 – Oct 7, 2027 · Cook County Assessor's OfficeMedian home assessment $40,000
  • New TrierForecastExpected Jun 5, 2027 – Aug 19, 2027 · Cook County Assessor's OfficeMedian home assessment $112,633
  • NilesForecastExpected Dec 9, 2026 – Jan 13, 2027 · Cook County Assessor's OfficeMedian home assessment $38,250
  • North ChicagoForecastExpected Nov 24, 2026 – Dec 30, 2026 · Cook County Assessor's OfficeMedian home assessment $135,400
  • NorthfieldForecastExpected Jul 31, 2027 – Nov 3, 2027 · Cook County Assessor's OfficeMedian home assessment $75,929
  • Norwood ParkForecastExpected May 5, 2027 – Aug 2, 2027 · Cook County Assessor's OfficeMedian home assessment $38,000
  • Oak ParkForecastExpected Apr 7, 2027 – Jun 18, 2027 · Cook County Assessor's OfficeMedian home assessment $45,000
  • OrlandOpenNov 6, 2026 · Cook County Assessor's OfficeMedian home assessment $35,000
  • PalatineOpenNov 4, 2026 · Cook County Assessor's OfficeMedian home assessment $42,553
  • PalosForecastExpected Apr 23, 2027 – Aug 14, 2027 · Cook County Assessor's OfficeMedian home assessment $32,595
  • ProvisoOpenOct 27, 2026 · Cook County Assessor's OfficeMedian home assessment $24,000
  • RichForecastExpected Dec 8, 2026 – Jan 13, 2027 · Cook County Assessor's OfficeMedian home assessment $20,000
  • River ForestForecastExpected Mar 19, 2027 – Jun 2, 2027 · Cook County Assessor's OfficeMedian home assessment $69,000
  • RiversideForecastExpected Mar 25, 2027 – Jun 8, 2027 · Cook County Assessor's OfficeMedian home assessment $35,000
  • Rogers ParkForecastExpected Apr 17, 2027 – Jul 19, 2027 · Cook County Assessor's OfficeMedian home assessment $46,001
  • SchaumburgForecastExpected Nov 18, 2026 – Dec 23, 2026 · Cook County Assessor's OfficeMedian home assessment $37,259
  • South ChicagoForecastExpected Dec 2, 2026 – Jan 7, 2027 · Cook County Assessor's OfficeMedian home assessment $40,000
  • StickneyForecastExpected Aug 12, 2027 – Sep 12, 2027 · Cook County Assessor's OfficeMedian home assessment $23,000
  • ThorntonForecastExpected Nov 18, 2026 – Dec 23, 2026 · Cook County Assessor's OfficeMedian home assessment $12,000
  • West ChicagoForecastExpected Jun 20, 2027 – Aug 23, 2027 · Cook County Assessor's OfficeMedian home assessment $30,000
  • WheelingOpenOct 22, 2026 · Cook County Assessor's OfficeMedian home assessment $42,001
  • WorthOpenOct 15, 2026 · Cook County Assessor's OfficeMedian home assessment $23,000

What evidence counts in Cook County, and can the value go up?

What evidence counts in Cook County?

Similar homes (uniformity)

The Board of Review compares homes in the same neighborhood and classification, using building assessment divided by building square feet.

Recent sales

Sales of similar homes within the last 3 years, or your own arm's-length purchase in the past 3 years below the Assessor's value, can be used at the Board of Review.

Record errors and damage

Wrong property details or damage are also common grounds.

Photo

The Board of Review asks for a color photo of the front of your home taken within the last 12 months. At the Assessor, owners filing for their own home don't need one.

Can my assessment go up if I appeal?

At the Board of Review, yes: it can raise an assessment, but only after notifying the owner in writing and giving a chance to be heard. It can also act on its own motion or on a taxing district's complaint.

Exemptions to check first

Exemptions lower the taxable value without an appeal. Check that your bill lists the ones you qualify for.

Homeowner Exemption

Lowers the equalized assessed value (EAV) of an owner-occupied home by $10,000.

Senior Exemption (65+)

Lowers EAV by a further $8,000.

Senior Freeze

For owners 65+ with household income of $65,000 or less (2024 income, for tax year 2025). It holds the EAV at a fixed amount; it doesn't freeze the tax bill itself.

Longtime Homeowner Exemption

For long-time owners with household income of $100,000 or less (2024 income, for tax year 2025) whose assessment rose sharply. The Assessor mails applications to homes that may qualify.

Persons with Disabilities Exemption

Lowers EAV by $2,000 a year.

Veterans exemptions

Veterans with a service-connected disability get an EAV reduction set by their disability rating ($250,000 at 70% or more). Returning veterans get $5,000 off EAV for the year they return.

Ways to appeal in Cook County

You can file on your own for free, use an evidence packet and file it yourself, or hire an Illinois attorney. Tax consultants may not represent a homeowner at the Board of Review; companies and LLCs need an attorney there.

On your ownProperty Appeal packetAttorney
County filing feeNoneNoneNone
Our fee—Flat $39 (Core) or $69 (Full Season)Set by the attorney
Who filesYouYouThe attorney

What if the Assessor's record of my home is wrong?

You can report factual errors, such as square footage, building details or class, to the Assessor at any time, not only during your township's appeal window. A missing exemption on a bill already issued is fixed with a Certificate of Error.

Certificates of Error and record fixes in Cook County

What evidence can I use in Cook County?

Cook County Assessor's Office: Common grounds: your assessment is out of line with similar homes (uniformity), the value is too high (overvaluation), or the property details are wrong. Cook County Board of Review: Common grounds at the Board: lack of uniformity with similar homes, a recent purchase, recent sales of similar homes, factual errors, or damage.

Evidence acceptedCook County Assessor's Office
Common grounds: your assessment is out of line with similar homes (uniformity), the value is too high (overvaluation), or the property details are wrong.[25]
Evidence acceptedCook County Board of Review
Common grounds at the Board: lack of uniformity with similar homes, a recent purchase, recent sales of similar homes, factual errors, or damage.[21]
Evidence acceptedCook County Board of Review · Market evidence
Sales of similar homes within the last 3 years can be used as evidence.[21]
Evidence acceptedCook County Board of Review · Recent purchase
A purchase in the past 3 years, at arm's length and below the Assessor's value, can support a reduction (closing documents).[21]
Evidence acceptedIllinois Property Tax Appeal Board
PTAB grounds: market value (recent sale, comparable sales, appraisal, recent construction), equity/uniformity, or a legal argument.[18]
Evidence ruleCook County Assessor's Office · Appraisals
Appraisals should be recent (within the reassessment period or no more than 2 years before January 1) and USPAP compliant.[4]
Evidence ruleCook County Assessor's Office · Comparable properties
If you use comparable properties: at least 3 are required and 5 are recommended.[4]
Evidence ruleCook County Assessor's Office · Comparable properties — location
Comparable properties should be in your assessment neighborhood and similar to your home.[25]
Evidence ruleCook County Assessor's Office · Photographs
A dated front photo is required, except for owners filing for their own home.[4]
Evidence ruleCook County Assessor's Office · Recent purchase
If the property sold within two years before January 1 of the appeal year, the sale date and price must be disclosed.[4]
Evidence ruleCook County Assessor's Office · Requested value
The filer must state the estimated fair market value they believe is correct.[4]
Evidence ruleCook County Board of Review · Appraisals
Appraisals must be by an Illinois-licensed or certified appraiser and follow USPAP.[5]
Evidence ruleCook County Board of Review · Written brief
Every filer must submit a brief (a short written explanation) with the evidence.[5]
Evidence ruleCook County Board of Review · Comparable properties — location
Compare your home with properties in the same neighborhood and the same classification code.[21]
Evidence ruleCook County Board of Review · Hearing documents
With a hearing, file your supporting documents by the Board's deadline after your township closes; they may include a current exterior photo and the PINs of the homes you compare.[23]
Evidence ruleCook County Board of Review · Photographs
Include a color photo of the front of the property taken within the last 12 months.[5]
Evidence ruleCook County Board of Review · Photo date
Mark the date each photo was taken clearly on its back; photos of the homes you compare are strongly encouraged.[2]
Evidence ruleCook County Board of Review · Recent purchase
A purchase within three years of the January 1 lien date must be disclosed with the sales documents.[5]
Evidence ruleCook County Board of Review · Signed statement
Owners who add evidence are encouraged to include a signed statement of the reasons they believe the property is over-assessed.[23]
Evidence ruleCook County Board of Review · Uniformity measure
Uniformity is compared as building assessment divided by building square feet.[21]
Evidence ruleIllinois Property Tax Appeal Board · After petition
Without an extension request filed with the petition, the PTAB accepts no evidence after the petition is filed.[3]
Evidence ruleIllinois Property Tax Appeal Board · Appraisals
PTAB does not require an appraisal; it notes that a letter stating only a conclusion of value is not an appraisal.[18]
Evidence ruleIllinois Property Tax Appeal Board · Written brief
A PTAB petition must state the facts behind the objection; a legal argument needs a brief filed with the petition.[3]
Evidence ruleIllinois Property Tax Appeal Board · Comparable properties
For an equity (uniformity) appeal, submit at least three comparable properties from your neighborhood.[18]
Evidence ruleIllinois Property Tax Appeal Board · Comps definition
PTAB describes a comparable property as one like yours in location, size and age, construction, and style.[18]
Evidence ruleIllinois Property Tax Appeal Board · New evidence
PTAB reviews the case fresh and is not limited to the evidence given to the Board of Review.[26]
Evidence ruleIllinois Property Tax Appeal Board · Photographs
The PTAB rules say a photo of the property should be included with the petition if it helps explain the appeal.[3]
Evidence ruleIllinois Property Tax Appeal Board · Rebuttal
PTAB rebuttal evidence can't add new evidence such as an appraisal or newly found comparable properties.[12]
Evidence ruleIllinois Property Tax Appeal Board · Recent purchase
For a recent-purchase argument at PTAB, include the settlement statement, the transfer declaration or the sale contract.[18]
Evidence ruleIllinois Property Tax Appeal Board · Requested value
The PTAB petition must list the Board of Review's land, building and total assessed values and the land, building and total values the owner claims are correct.[3]
Evidence not acceptedCook County Board of Review
The Board only hears the current tax year; prior years cannot be appealed there.[2]
Evidence not acceptedIllinois Property Tax Appeal Board
PTAB decides assessments only; it cannot review the tax bill amount or tax rate.[27]

Can my assessment go up if I appeal in Cook County?

Cook County Board of Review: The Board of Review can raise an assessment, but only after notifying the owner in writing and giving a chance to be heard. Cook County Board of Review · Own motion: The Board may also change an assessment on its own motion, and taxing districts may file complaints, after notice to the owner.

Can the value go up?Cook County Board of Review
The Board of Review can raise an assessment, but only after notifying the owner in writing and giving a chance to be heard.[28]
Can the value go up?Cook County Board of Review · Own motion
The Board may also change an assessment on its own motion, and taxing districts may file complaints, after notice to the owner.[29]
Does a reduction carry forward?Illinois Property Tax Appeal Board
If PTAB lowers the assessment of an owner-occupied home, the lower value stays for the rest of the reassessment period (subject to equalization) unless the home sells.[30]

Which exemptions can lower my bill without an appeal?

The Persons with Disabilities Exemption lowers EAV by $2,000 a year (tax year 2025). Homeowner Exemption: lowers the equalized assessed value (EAV) of an owner-occupied home by $10,000 (tax year 2025).

Disabled persons
The Persons with Disabilities Exemption lowers EAV by $2,000 a year.[31] (latest published: tax year 2025)
Homeowner exemption
Homeowner Exemption: lowers the equalized assessed value (EAV) of an owner-occupied home by $10,000.[32] (latest published: tax year 2025)
Returning veterans
The Returning Veterans Exemption lowers EAV by $5,000 for the year a veteran returns from active duty in armed conflict.[33] (latest published: tax year 2025)
Senior exemption
Senior Exemption (65+): lowers EAV by a further $8,000.[34] (latest published: tax year 2025)
Senior assessment freeze
Senior Freeze: for owners 65+ with household income of $65,000 or less (2024 income for tax year 2025).[35] (latest published: tax year 2025)
How the senior freeze works
The Senior Freeze holds the EAV at a fixed amount; it does not freeze the tax bill itself.[35] (latest published: tax year 2025)
Veterans disabilities
The Veterans with Disabilities Exemption depends on the disability rating; veterans rated 70% or more receive a $250,000 EAV reduction.[36] (latest published: tax year 2025)
Assessment limitsLongtime homeowner
The Longtime Homeowner Exemption (tax year 2025) needs household income of $100,000 or less for 2024 and a large assessment increase; the Assessor mails applications to properties that may qualify.[37] (latest published: tax year 2025)

What do Cook County property taxes and assessments look like?

Figures from public records and the Census, each with its source. They describe the county's homes as a group, not the value of any one home.

What do homeowners in Cook County pay in property tax?

The median owner-occupied home in Cook County was worth $324,500, and the median property tax its owners paid was $6,191 a year, according to the Census Bureau's American Community Survey.

Median home value
$324,500
Margin of error ±$1,460.
Median property tax paid per year
$6,191
Margin of error ±$30.
Median tax as a share of median value
1.91%
A ratio of two medians, not a tax rate. Your own bill depends on your assessment and local levies.
Owner-occupied homes
1,212,570
Margin of error ±7,287.

These are survey estimates of what owners reported about their own homes. They are not assessed values, not tax rates, and not an opinion of what any home is worth.

They cannot tell you whether your own assessment is fair. That takes a comparison with similar homes, which we offer only in counties we have researched.

From the county's assessment and appeal records

Homes in the county's assessment records
1,077,232
Median assessed value
$30,000
Middle half of assessed values
$20,000 to $44,000
Appeals lowered at the assessor
18% of 186,267; median cut 5.8%
tax year 2025 results; past results, not a prediction
Appeals lowered at the board of review
51% of 255,838; median cut 6.6%
tax year 2025 results; past results, not a prediction

Source: The county's open assessment data, aggregated by us (tax year 2025 values after the board of review). Our calculation from public records; not an opinion of any home's value.

How Cook County home assessments are spread

Assessed values of 1,077,232 homes in the property classes our free check covers (202, 203, 204, 205, 206 and 8 more), tax year 2025 values after the Board of Review. Half are between $20,000 and $44,000; the median is $30,000. The last bar holds everything above it.Source: Assessment records from the county's open data (tax year 2025 values after the Board of Review), retrieved Sep 25, 2026; our calculation.

Median home value: Cook County compared

  1. Cook County$324,500
  2. Typical Illinois county$134,650
  3. Typical US county$185,300

Cook County $324,500; Typical US county $185,300; Typical Illinois county $134,650

Census survey medians for owner-occupied homes. "Typical" is the middle county of the 102 in Illinois and of all US counties.Source: U.S. Census Bureau, American Community Survey 5-year estimates, table B25077.

Median property tax paid: Cook County compared

  1. Cook County$6,191
  2. Typical Illinois county$2,431
  3. Typical US county$1,619

Cook County $6,191 a year; Typical Illinois county $2,431 a year; Typical US county $1,619 a year

Census survey medians for owner-occupied homes. "Typical" is the middle county of the 102 in Illinois and of all US counties.Source: U.S. Census Bureau, American Community Survey 5-year estimates, table B25103.

Median home assessment by township

  1. North Chicago$135,400
  2. New Trier$112,633
  3. Lake View$89,642
  4. Barrington$77,000
  5. Northfield$75,929
  6. River Forest$69,000
  7. Evanston$61,000
  8. Lemont$47,001
  9. Rogers Park$46,001
  10. Oak Park$45,000
  11. Palatine$42,553
  12. Wheeling$42,001
  13. Elk Grove$40,000
  14. Maine$40,000
  15. South Chicago$40,000
  16. Jefferson$38,977
  17. Niles$38,250
  18. Norwood Park$38,000
  19. Schaumburg$37,259
  20. Orland$35,000
  21. Riverside$35,000
  22. Lyons$33,000
  23. Palos$32,595
  24. Hanover$31,000
  25. Leyden$30,000
  26. West Chicago$30,000
  27. Berwyn$25,000
  28. Proviso$24,000
  29. Stickney$23,000
  30. Worth$23,000
  31. Cicero$22,000
  32. Rich$20,000
  33. Lake$19,861
  34. Bremen$19,353
  35. Bloom$14,168
  36. Hyde Park$13,701
  37. Calumet$13,000
  38. Thornton$12,000

Median assessed value by township: highest North Chicago ($135,400), lowest Thornton ($12,000).

Median assessed value of homes in the property classes our free check covers (202, 203, 204, 205, 206 and 8 more) for each township with at least 50 such homes, tax year 2025 values after the Board of Review.Source: Assessment records from the county's open data (tax year 2025 values after the Board of Review), retrieved Sep 25, 2026; our calculation.

How much home assessments changed, by township

  1. River Forest+27.8%
  2. Berwyn+24.0%
  3. Oak Park+22.2%
  4. Stickney+21.1%
  5. Riverside+20.4%
  6. Cicero+20.0%
  7. Palos+20.0%
  8. Elk Grove0.0%
  9. Evanston0.0%
  10. Lake View0.0%
  11. Maine0.0%
  12. New Trier0.0%
  13. Norwood Park0.0%
  14. Rogers Park0.0%

Median change in assessed value from tax year 2025 values after the Board of Review to tax year 2026 Assessor-certified values: Berwyn +24.0%, Cicero +20.0%, Elk Grove 0.0%, Evanston 0.0%, Maine 0.0%, New Trier 0.0% and more.

Median change per home from tax year 2025 values after the Board of Review to tax year 2026 Assessor-certified values, for homes with a value at both stages. 14 townships have the newer values so far.Source: Assessment records from the county's open data (tax year 2025 values after the Board of Review), retrieved Sep 25, 2026; our calculation.

What happened to Cook County appeals in tax year 2025

  1. All townships · Assessor18% lowered of 186,267
  2. All townships · Board of Review51% lowered of 255,838
  3. Schaumburg62% lowered of 9,816
  4. Elk Grove62% lowered of 6,542
  5. Norwood Park61% lowered of 3,038
  6. Leyden60% lowered of 6,282
  7. Maine60% lowered of 14,065
  8. Northfield59% lowered of 14,528
  9. Niles58% lowered of 12,425
  10. Wheeling58% lowered of 15,658
  11. Evanston57% lowered of 6,584
  12. New Trier55% lowered of 12,316
  13. Palatine54% lowered of 12,196
  14. Cicero52% lowered of 1,732
  15. Hanover52% lowered of 6,429
  16. Barrington52% lowered of 2,988
  17. Lake52% lowered of 14,427
  18. Jefferson48% lowered of 23,864
  19. West Chicago47% lowered of 12,339
  20. Calumet47% lowered of 552
  21. Lake View45% lowered of 8,901
  22. Oak Park45% lowered of 3,446
  23. Thornton44% lowered of 7,125
  24. Berwyn44% lowered of 2,770
  25. Bloom44% lowered of 2,867
  26. Rogers Park44% lowered of 2,166
  27. Stickney44% lowered of 1,658
  28. Proviso44% lowered of 6,233
  29. Hyde Park43% lowered of 5,401
  30. Bremen43% lowered of 4,539
  31. South Chicago43% lowered of 3,421
  32. Worth42% lowered of 5,457
  33. Rich41% lowered of 3,889
  34. River Forest41% lowered of 1,115
  35. Lyons40% lowered of 6,550
  36. Riverside38% lowered of 1,067
  37. Orland37% lowered of 6,372
  38. Palos36% lowered of 2,855
  39. North Chicago32% lowered of 2,241
  40. Lemont31% lowered of 1,984

All townships · Assessor: 18% of 186,267 appeals lowered (median cut 5.8%); All townships · Board of Review: 51% of 255,838 appeals lowered (median cut 6.6%)

Share of appeals on homes in the property classes our free check covers (202, 203, 204, 205, 206 and 8 more) that were lowered, unchanged or raised: county-wide at each stage, then at the Board of Review by township.Source: public appeal results for tax year 2025 from the county's open data, retrieved Sep 25, 2026; our calculation. Past results, not a prediction for any home.

Cook County filing windows on a calendar

  1. Hyde Park TownshipOct 8, 2026 · Cook County Assessor's Office · Open now
  2. Leyden TownshipOct 14, 2026 · Cook County Assessor's Office · Open now
  3. Worth TownshipOct 15, 2026 · Cook County Assessor's Office · Open now
  4. Wheeling TownshipOct 22, 2026 · Cook County Assessor's Office · Open now
  5. Proviso TownshipOct 27, 2026 · Cook County Assessor's Office · Open now
  6. Lake TownshipOct 29, 2026 · Cook County Assessor's Office · Open now
  7. Palatine TownshipNov 4, 2026 · Cook County Assessor's Office · Open now
  8. Orland TownshipNov 6, 2026 · Cook County Assessor's Office · Open now
  9. Jefferson TownshipNov 12, 2026 · Cook County Assessor's Office · Open now
  10. Schaumburg TownshipExpected Nov 18, 2026 – Dec 23, 2026 · Cook County Assessor's Office · Forecast, not an official date
  11. Thornton TownshipExpected Nov 18, 2026 – Dec 23, 2026 · Cook County Assessor's Office · Forecast, not an official date
  12. North Chicago TownshipExpected Nov 24, 2026 – Dec 30, 2026 · Cook County Assessor's Office · Forecast, not an official date

The dashed line marks today.

Hyde Park Township: Oct 8, 2026; Leyden Township: Oct 14, 2026; Worth Township: Oct 15, 2026; Wheeling Township: Oct 22, 2026; Proviso Township: Oct 27, 2026; Lake Township: Oct 29, 2026; Palatine Township: Nov 4, 2026; Orland Township: Nov 6, 2026; Jefferson Township: Nov 12, 2026; Schaumburg Township: Expected Nov 18, 2026 – Dec 23, 2026; Thornton Township: Expected Nov 18, 2026 – Dec 23, 2026; North Chicago Township: Expected Nov 24, 2026 – Dec 30, 2026

Each bar is a filing window from its opening day to its last day (the 12 soonest of 51). Forecasts show the expected closing range and are not official dates.Source: the official calendars and rules cited in the sources list below.

How Cook County property tax is figured

Homes (class 2) are assessed at 10% of the Assessor's estimated market value. The state then applies an equalization factor (the "multiplier"); the final 2025 factor for Cook County is 3.0300. The assessed value times the multiplier is the equalized assessed value (EAV). Exemptions lower the EAV, and local tax rates are applied to what is left.

Each bill uses a composite rate: the Cook County Clerk adds up the rates of every taxing district that serves your property (schools, city or village, parks and others).

For tax year 2025, the first installment was due April 1, 2026 and the second-installment bill was due October 1, 2026.

The first installment is 55% of the previous year's total bill. The second installment can't be figured until the Board of Review finishes all 38 townships, so an appeal decision comes before that bill.

You can download your bill and pay it on the Cook County Treasurer's site by PIN or address.

Is my township being reassessed in 2026?

Cook County reassesses each area once every three years. In 2026 the south and west suburbs are being reassessed. The City of Chicago is next reassessed in 2027.

Cook County homes at a glance

Median value of owner-occupied homes
$324,500
Median real estate taxes paid
$6,191 a year
Owner-occupied homes
about 1,212,570

How often is property reassessed in Cook County?

Cook County reassesses each property once every three years, by region. In 2026 the south and west suburbs are being reassessed (17 townships); the north suburbs and Chicago are not.

Reassessment cycle
Cook County reassesses each property once every three years, by region.[38]
Area reassessed this year
In 2026 the south and west suburbs are being reassessed (17 townships); the north suburbs and Chicago are not.[38]
Valuation date
Assessments refer to the property as of January 1 of the tax year (the lien date).[5]
Level of assessment
Homes (class 2) are assessed at 10% of the estimated market value.[39]
State equalization factor
The final 2025 state equalization factor (multiplier) for Cook County is 3.0300.[40] (latest published: tax year 2025)
State equalization factorTentative
The tentative 2025 Cook County multiplier announced in April 2026 was 2.8683 (replaced by the final factor).[41] (latest published: tax year 2025)

What do home values and property taxes look like in Cook County?

Effective property tax rate: 1.73% (Tax Foundation, 2026 edition). Median value of owner-occupied homes: $324,500 (Census ACS 2020-2024).

Effective tax rate
Effective property tax rate: 1.73% (Tax Foundation, 2026 edition).[42]
Median home value
Median value of owner-occupied homes: $324,500 (Census ACS 2020-2024).[43]
Median real estate taxes
Median real estate taxes paid by homeowners: $6,191 a year (Census ACS 2020-2024).[44]
Median tax as a share of median home value
Median tax divided by median home value: about 1.91% (a rough ratio, not an official rate).[44]
Owner-occupied homes
Owner-occupied homes: about 1,212,570 (Census ACS 2020-2024).[45]
Property tax rateComposite
Each tax bill uses a composite (aggregate) rate: the Cook County Clerk adds up the rates of every taxing district that serves the property.[46]

Homes in Cook County

From the Census Bureau's American Community Survey: how old the homes are, what kind they are, what owners say they are worth and the property taxes they pay. These figures describe all homes together, not any one home.

Median year built
1961
All housing units, owned and rented
Single-family houses, detached or attached
45%
of 2,276,493 housing units
Owned homes with a mortgage or similar loan
62%
of 1,212,570 owner-occupied homes

Home values reported by owners

  1. Less than $50,0004%
  2. $50,000 to $99,9993%
  3. $100,000 to $199,99915%
  4. $200,000 to $299,99923%
  5. $300,000 to $399,99921%
  6. $400,000 to $499,99913%
  7. $500,000 to $749,99912%
  8. $750,000 to $999,9995%
  9. $1,000,000 to $1,999,9994%
  10. $2,000,000 or more1%

Home values reported by owners in Cook County: Less than $50,000 4%; $50,000 to $99,999 3%; $100,000 to $199,999 15%; $200,000 to $299,999 23%; $300,000 to $399,999 21%; $400,000 to $499,999 13%; $500,000 to $749,999 12%; $750,000 to $999,999 5%; $1,000,000 to $1,999,999 4%; $2,000,000 or more 1%.

Share of owner-occupied homes in each value range. Owners give this value in the survey; it is not the assessed value.Source: U.S. Census Bureau, American Community Survey, 2020–2024 5-year estimates, table B25075.

Property taxes owners pay a year

  1. No real estate taxes4%
  2. Less than $8003%
  3. $800 to $1,4994%
  4. $1,500 to $1,9993%
  5. $2,000 to $2,9998%
  6. $3,000 or more77%

Property taxes owners pay a year in Cook County: No real estate taxes 4%; Less than $800 3%; $800 to $1,499 4%; $1,500 to $1,999 3%; $2,000 to $2,999 8%; $3,000 or more 77%.

Share of owner-occupied homes by the real estate taxes paid in a year, with or without a mortgage.Source: U.S. Census Bureau, American Community Survey, 2020–2024 5-year estimates, table B25102.

Source: U.S. Census Bureau, American Community Survey (2020–2024 5-year estimates, tables B25075, B25102, B25035, B25024 and B25081), retrieved Oct 1, 2026. Survey estimates have a margin of error.

More questions about Cook County property tax appeals

When is the Cook County property tax appeal deadline?

The Cook County Assessor's Office window closes October 8, 2026. Cook County Assessor's Office: Assessor appeals stay open at least 30 business days after the township's notices go out. The exact last day is posted on the Assessor's calendar and printed on the notice.[1][38]

Is there a fee to file a property tax appeal in Cook County?

There is no fee to appeal to the Assessor.[9]

Where do I file a Board of Review appeal in Cook County?

File online with the Assessor's SmartFile system.[4]

Can my assessed value go up if I appeal in Cook County?

The Board of Review can raise an assessment, but only after notifying the owner in writing and giving a chance to be heard.[28]

Common questions

Can I appeal my Cook County property taxes online?

Yes. The Assessor takes appeals online through SmartFile, and the Board of Review has an online filing portal.

Can I appeal on my own in Cook County?

Not for your own home. No attorney is needed at the Assessor, and owners may appear for property in their own name at the Board of Review. Companies, LLCs and condo associations need an attorney at the Board of Review. Not legal advice.

Can I skip the Assessor and go to the Board of Review?

Yes. You can appeal to the Board of Review whether or not you appealed to the Assessor, and the Board isn't bound by the Assessor's decision.

Is there a hearing?

At the Board of Review, owner hearings are by phone and optional; you can waive one without penalty.

Can I appeal a past year?

Not at the Board of Review; it hears the current tax year only.

What other rules apply in Cook County?

Cook County Assessor's Office · Property characteristics: Factual errors in the Assessor's record (square footage, building characteristics, class, data-entry errors) can be reported any time via the Contact Us page, e-mail, mail, in person, or in SmartFile with an appeal. Cook County Assessor's Office · Square footage: The Assessor measures building square footage around the home's exterior, not room-by-room living space.

Record correctionCook County Assessor's Office · Property characteristics
Factual errors in the Assessor's record (square footage, building characteristics, class, data-entry errors) can be reported any time via the Contact Us page, e-mail, mail, in person, or in SmartFile with an appeal.[4]
Record correctionCook County Assessor's Office · Square footage
The Assessor measures building square footage around the home's exterior, not room-by-room living space.[50]
Record correctionCook County Assessor's Office · How a corrected record changes the value
The Assessor notes that many characteristic corrections do not change the assessed value.[4]
Record correctionCook County Assessor's Office · Exemption
If an eligible homestead exemption was missing from a paid bill for tax years 2021-2025, the owner can apply for a refund through a Certificate of Error, online or by mail.[51]
Record correctionCook County Assessor's Office · Exemption refund timing
For a missing Homeowner Exemption, the Assessor's FAQ says the Treasurer's refund follows the Certificate of Error in about 6 to 8 weeks.[52]
Record correctionCook County Assessor's Office · Removing an exemption
An owner who is no longer eligible for a homestead exemption can apply to the Assessor to remove it.[53]
Record correctionCook County Assessor's Office · Proof
A valuation Certificate of Error needs the application and the same supporting documents as a current-year appeal; missing documents can lead to denial.[4]
Record correctionCook County Assessor's Office · Proof for a characteristics correction
To correct characteristics such as square footage, the Assessor asks for documents like a plat of survey or photos.[54]
Record correctionCook County Assessor's Office · Proof for an exemption correction
An exemption Certificate of Error needs a photo ID and documents showing eligibility in the tax year applied for.[51]
Record correctionCook County Assessor's Office · Proof with the first filing
The Assessor does not re-review Certificate of Error decisions, so all proof should be included with the first filing.[4]
Record correctionCook County Assessor's Office · Route
A Certificate of Error lets the Cook County Assessor correct a tax bill that was already issued, for a missing exemption or an assessed value.[51]
Record correctionCook County Assessor's Office · Board of Review endorsement
If the Board of Review already reviewed the assessment, it must also approve the Certificate of Error.[51]
Record correctionCook County Assessor's Office · How to ask for a correction
A valuation Certificate of Error can be filed with a current-year appeal in SmartFile (recommended) or on its own at any time by e-mail to the Assessor.[55]
Record correctionCook County Assessor's Office · Certificate of Error or a PTAB or court appeal
The Assessor's rules say state law generally bars filing both a Certificate of Error and a PTAB or Circuit Court appeal for the same tax year.[4]
Record correctionCook County Assessor's Office · Which tax years can be corrected
Most valuation Certificates of Error can currently be filed for tax years 2025, 2024, 2023 and 2022.[55]
Record correctionCook County Assessor's Office · How long a correction takes
The Assessor says valuation Certificates of Error can take up to two years to issue and certify; exemption ones are usually faster.[55]
Paying the tax while you appealIllinois Property Tax Appeal Board
A PTAB appeal does not delay the tax bill; taxes still come due and should be paid on time.[18]

Property tax guides for Cook County homeowners

Counties next to Cook County

Illinois property tax appeals: all counties

Check a Cook County home free

Check my property

You decide and file yourself.

Where do these facts come from?

  1. [1]35 ILCS 200/12-55 - Illinois Property Tax Code (ILGA; Wayback capture 2026-01-09)Statute or regulation · last checked Sep 24, 2026
  2. [2]Frequently Asked Questions - Cook County Board of ReviewOfficial guide or FAQ · last checked Sep 25, 2026
  3. [3]86 Ill. Adm. Code 1910.30 - Property Tax Appeal Board rules (JCAR/ILGA; Wayback capture 2025-03-21)Statute or regulation · last checked Sep 25, 2026
  4. [4]Official Appeal Rules of the Cook County Assessor (2026 Appeal Rules)Official notice, form, calendar or rules · last checked Sep 24, 2026
  5. [5]Cook County Board of Review Official Rules (last updated July 27, 2026)Official notice, form, calendar or rules · last checked Sep 24, 2026
  6. [6]Assessor's Office Locations (incl. 2026 office holidays) - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 24, 2026
  7. [7]Due Dates - Cook County Treasurer's OfficeOfficial notice, form, calendar or rules · last checked Sep 25, 2026
  8. [8]Property Tax Exemptions - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  9. [9]Overview of How Appeals Work - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 24, 2026
  10. [10]35 ILCS 200/16-110 - Illinois Property Tax Code (ILGA; Wayback capture 2022-09-30)Statute or regulation · last checked Sep 24, 2026
  11. [11]86 Ill. Adm. Code 1910.40 - Property Tax Appeal Board rules (JCAR/ILGA; Wayback capture 2026-01-13)Statute or regulation · last checked Sep 25, 2026
  12. [12]86 Ill. Adm. Code 1910.66 - Property Tax Appeal Board rules (JCAR/ILGA; Wayback capture 2026-01-14)Statute or regulation · last checked Sep 25, 2026
  13. [13]Assessment & Appeal Calendar (page last updated 9/24/26) - Cook County Assessor's OfficeOfficial notice, form, calendar or rules · last checked Oct 1, 2026
  14. [14]35 ILCS 200/16-160 - Illinois Property Tax Code (ILGA; Wayback capture 2026-01-18)Statute or regulation · last checked Sep 24, 2026
  15. [15]35 ILCS 200/23-10 - Illinois Property Tax Code (ILGA; Wayback capture 2026-01-18)Statute or regulation · last checked Sep 24, 2026
  16. [16]Learn about Reassessments (Valuation Reports) - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  17. [17]Cook County Board of Review Opens Second Group of Townships for 2026 Property Tax Appeal Season (Aug 27, 2026)Official press release · last checked Sep 24, 2026
  18. [18]Frequently Asked Questions - Illinois Property Tax Appeal Board (Wayback capture 2026-05-20)Official guide or FAQ · last checked Sep 25, 2026
  19. [19]Forms & Brochures - Illinois Property Tax Appeal Board (Wayback capture 2026-03-09)Official guide or FAQ · last checked Sep 25, 2026
  20. [20]2026 Real Estate Assessed Valuation Complaint (PDF) - Cook County Board of ReviewOfficial notice, form, calendar or rules · last checked Sep 24, 2026
  21. [21]How to Present a Case - Cook County Board of ReviewOfficial guide or FAQ · last checked Sep 24, 2026
  22. [22]86 Ill. Adm. Code 1910.70 - Property Tax Appeal Board rules (JCAR/ILGA; Wayback capture 2026-07-01)Statute or regulation · last checked Sep 24, 2026
  23. [23]Residential Hearings - Cook County Board of ReviewOfficial guide or FAQ · last checked Sep 24, 2026
  24. [24]86 Ill. Adm. Code 1910.67 - Property Tax Appeal Board rules (JCAR/ILGA; Wayback capture 2026-05-27)Statute or regulation · last checked Sep 25, 2026
  25. [25]Residential Appeals - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 24, 2026
  26. [26]35 ILCS 200/16-180 - Illinois Property Tax Code (ILGA; Wayback capture 2025-03-28)Statute or regulation · last checked Sep 24, 2026
  27. [27]Home - Illinois Property Tax Appeal Board (Wayback capture 2026-08-31)Official guide or FAQ · last checked Sep 24, 2026
  28. [28]35 ILCS 200/16-120 - Illinois Property Tax Code (ILGA; Wayback capture 2025-04-17)Statute or regulation · last checked Sep 24, 2026
  29. [29]35 ILCS 200/16-95 - Illinois Property Tax Code (ILGA; Wayback capture 2025-12-22)Statute or regulation · last checked Sep 24, 2026
  30. [30]35 ILCS 200/16-185 - Illinois Property Tax Code (ILGA; Wayback capture 2025-12-22)Statute or regulation · last checked Sep 24, 2026
  31. [31]Persons with Disabilities Exemption - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  32. [32]Homeowner Exemption - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 24, 2026
  33. [33]Returning Veterans Exemption - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  34. [34]Senior Exemption - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 24, 2026
  35. [35]Low-Income Senior Freeze Exemption - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 24, 2026
  36. [36]Homestead Exemption for Veterans with Disabilities - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  37. [37]Longtime Homeowner Exemption - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  38. [38]Assessment & Appeal Calendar (page last updated 9/22/26) - Cook County Assessor's OfficeOfficial notice, form, calendar or rules · last checked Sep 24, 2026
  39. [39]Your Assessment Notice and Tax Bill - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 24, 2026
  40. [40]Illinois Department of Revenue announces 2025 Cook County property tax equalization factor - Chicago City WireSecondary source · last checked Sep 24, 2026
  41. [41]2025 Cook County Tentative Multiplier Announced - Illinois Department of Revenue (Wayback capture 2026-06-08)Official press release · last checked Sep 24, 2026
  42. [42]Property Taxes by State and County, 2026 - Tax Foundation (Table 1)Secondary source · last checked Sep 24, 2026
  43. [43]ACS 2020-2024 5-year table-based summary file, table B25077 (U.S. Census Bureau)Official notice, form, calendar or rules · last checked Sep 24, 2026
  44. [44]ACS 2020-2024 5-year table-based summary file, table B25103 (U.S. Census Bureau)Official notice, form, calendar or rules · last checked Sep 24, 2026
  45. [45]ACS 2020-2024 5-year table-based summary file, table B25003 (U.S. Census Bureau)Official notice, form, calendar or rules · last checked Sep 24, 2026
  46. [46]How the Illinois Property Tax System Works (Cook County Treasurer, October 2025 update)Official guide or FAQ · last checked Sep 25, 2026
  47. [47]Your Property Tax Overview - Cook County Treasurer's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  48. [48]File an Appeal Online - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  49. [49]Home Page - Cook County Board of ReviewOfficial guide or FAQ · last checked Sep 25, 2026
  50. [50]I measured the rooms of my house and came up with much less square footage in terms of living space than the Assessor's Office has listed. What should I do? - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  51. [51]Certificates of Error - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  52. [52]I did not receive my Homeowner Exemption on my tax bill. What do I do? - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  53. [53]Erroneous Exemptions - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  54. [54]Update Property Characteristics - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  55. [55]Certificates of Error for Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Sep 25, 2026
  56. [56]Cook County Board of Review Dates and Deadlines 2026 Session (PDF, created 2026-09-14)Official notice, form, calendar or rules · last checked Sep 24, 2026
  57. [57]2025 Assessment Calendar (PDF) - Cook County Assessor's Office (Wayback Machine capture 2026-05-11)Official notice, form, calendar or rules · last checked Sep 24, 2026
  58. [58]Detailed Methodology Reports Released for Riverside Township - Cook County Assessor's Office (press release, February 18, 2020)Official guide or FAQ · last checked Oct 1, 2026
  59. [59]Reassessments Begin in Cook County’s South and West Suburbs - Cook County Assessor's Office (press release, April 7, 2023)Official guide or FAQ · last checked Oct 1, 2026
  60. [60]Detailed Methodology Reports Released for Oak Park Township - Cook County Assessor's Office (press release, March 4, 2020)Official guide or FAQ · last checked Oct 1, 2026
  61. [61]Property Values for Oak Park Township Released - Cook County Assessor's Office (press release, April 19, 2023)Official guide or FAQ · last checked Oct 1, 2026
  62. [62]Calumet Township Properties Reassessed - Cook County Assessor's Office (press release, May 6, 2020)Official guide or FAQ · last checked Oct 1, 2026
  63. [63]Property Values for Calumet Township Released - Cook County Assessor's Office (press release, April 7, 2023)Official guide or FAQ · last checked Oct 1, 2026
  64. [64]Property Reassessments Begin in Cook County’s North Suburbs - Cook County Assessor's Office (press release, July 7, 2022)Official guide or FAQ · last checked Oct 1, 2026
  65. [65]2025 Reassessment of North Suburbs Begins in Norwood Park Township - Cook County Assessor's Office (press release, March 26, 2025)Official guide or FAQ · last checked Oct 1, 2026
  66. [66]Reassessment of South Suburbs Begins with River Forest Township - Cook County Assessor's Office (press release, February 12, 2020)Official guide or FAQ · last checked Oct 1, 2026
  67. [67]Property Values for River Forest Township Released - Cook County Assessor's Office (press release, May 11, 2023)Official guide or FAQ · last checked Oct 1, 2026
  68. [68]Assessor Fritz Kaegi releases first property reassessments for City of Chicago - Cook County Assessor's Office (press release, June 16, 2021)Official guide or FAQ · last checked Oct 1, 2026
  69. [69]Property Values for Rogers Park Township Released - Cook County Assessor's Office (press release, March 21, 2024)Official guide or FAQ · last checked Oct 1, 2026
  70. [70]Evanston Township Property Values Released - Cook County Assessor's Office (press release, August 11, 2022)Official guide or FAQ · last checked Oct 1, 2026
  71. [71]Property Values for Evanston Township Released - Cook County Assessor's Office (press release, April 11, 2025)Official guide or FAQ · last checked Oct 1, 2026
  72. [72]New Trier Township Property Values Released - Cook County Assessor's Office (press release, July 21, 2022)Official guide or FAQ · last checked Oct 1, 2026
  73. [73]Property Values for New Trier Township Released - Cook County Assessor's Office (press release, April 24, 2025)Official guide or FAQ · last checked Oct 1, 2026
  74. [74]Berwyn Township Properties Reassessed - Cook County Assessor's Office (press release, May 28, 2020)Official guide or FAQ · last checked Oct 1, 2026
  75. [75]Property Values for Berwyn Township Released - Cook County Assessor's Office (press release, May 4, 2023)Official guide or FAQ · last checked Oct 1, 2026
  76. [76]Property Values for Cicero Township Released - Cook County Assessor's Office (press release, April 2, 2023)Official guide or FAQ · last checked Oct 1, 2026
  77. [77]Lemont Township Properties Reassessed - Cook County Assessor's Office (press release, June 12, 2020)Official guide or FAQ · last checked Oct 1, 2026
  78. [78]Property Values for Lemont Township Released - Cook County Assessor's Office (press release, May 19, 2023)Official guide or FAQ · last checked Oct 1, 2026
  79. [79]Assessor’s Office Releases Detailed Assessment Reports on Palos Township - Cook County Assessor's Office (press release, March 18, 2020)Official guide or FAQ · last checked Oct 1, 2026
  80. [80]Property Values for Palos Township Released - Cook County Assessor's Office (press release, July 26, 2023)Official guide or FAQ · last checked Oct 1, 2026
  81. [81]Maine Township Property Values Released - Cook County Assessor's Office (press release, September 13, 2022)Official guide or FAQ · last checked Oct 1, 2026
  82. [82]Property Values for Maine Township released - Cook County Assessor's Office (press release, June 6, 2025)Official guide or FAQ · last checked Oct 1, 2026
  83. [83]Elk Grove Township Property Values Released - Cook County Assessor's Office (press release, August 3, 2022)Official guide or FAQ · last checked Oct 1, 2026
  84. [84]Property Values for Elk Grove Township Released - Cook County Assessor's Office (press release, May 19, 2025)Official guide or FAQ · last checked Oct 1, 2026
  85. [85]Barrington Township Property Values Released - Cook County Assessor's Office (press release, July 12, 2022)Official guide or FAQ · last checked Oct 1, 2026
  86. [86]Property Values for Barrington Township Released - Cook County Assessor's Office (press release, July 7, 2025)Official guide or FAQ · last checked Oct 1, 2026
  87. [87]Property reassessments released for West Chicago Township - Cook County Assessor's Office (press release, July 27, 2021)Official guide or FAQ · last checked Oct 1, 2026
  88. [88]Property Values for West Chicago Township Released - Cook County Assessor's Office (press release, May 23, 2024)Official guide or FAQ · last checked Oct 1, 2026
  89. [89]Property Values for Stickney Township Released - Cook County Assessor's Office (press release, August 23, 2023)Official guide or FAQ · last checked Oct 1, 2026
  90. [90]Northfield Township Property Values Released - Cook County Assessor's Office (press release, October 5, 2022)Official guide or FAQ · last checked Oct 1, 2026
  91. [91]Property Values for Northfield Township Released - Cook County Assessor's Office (press release, June 20, 2025)Official guide or FAQ · last checked Oct 1, 2026
  92. [92]Property Values for Bremen Township Released - Cook County Assessor's Office (press release, September 20, 2023)Official guide or FAQ · last checked Oct 1, 2026
  93. [93]Property reassessments released for Lake View Township - Cook County Assessor's Office (press release, November 24, 2021)Official guide or FAQ · last checked Oct 1, 2026
  94. [94]Property Values for Lyons Township Released - Cook County Assessor's Office (press release, October 31, 2023)Official guide or FAQ · last checked Oct 1, 2026
  95. [95]Township Triennial Reassessment Schedule (PDF) - Cook County Board of ReviewOfficial notice, form, calendar or rules · last checked Oct 1, 2026
  96. [96]Barrington Township: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  97. [97]Cook County Township Assessors - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  98. [98]Board of Review 2025 Re-Review/Decision Dates (PDF, Rev.6/9/2026) - Cook County Board of ReviewOfficial notice, form, calendar or rules · last checked Oct 1, 2026
  99. [99]Berwyn: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  100. [100]Property Values for Berwyn Township Released - Cook County Assessor's Office (press release, May 27, 2026)Official guide or FAQ · last checked Oct 1, 2026
  101. [101]Property Values for Bloom Township Released - Cook County Assessor's Office (press release, July 5, 2023)Official guide or FAQ · last checked Oct 1, 2026
  102. [102]Bremen Township: Residential - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  103. [103]Property Values for Bremen Township Released - Cook County Assessor's Office (press release, August 14, 2026)Official guide or FAQ · last checked Oct 1, 2026
  104. [104]Calumet: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  105. [105]Cicero: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  106. [106]Property Values for Cicero Township Released - Cook County Assessor's Office (press release, June 18, 2026)Official guide or FAQ · last checked Oct 1, 2026
  107. [107]Elk Grove Township: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  108. [108]Evanston Township: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  109. [109]Hanover Township Property Values Released - Cook County Assessor's Office (press release, July 13, 2022)Official guide or FAQ · last checked Oct 1, 2026
  110. [110]Hanover Township: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  111. [111]Property Values for Hyde Park Township Released - Cook County Assessor's Office (press release, August 1, 2024)Official guide or FAQ · last checked Oct 1, 2026
  112. [112]Hyde Park: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  113. [113]Property Values for Jefferson Township Released - Cook County Assessor's Office (press release, October 2, 2024)Official guide or FAQ · last checked Oct 1, 2026
  114. [114]Jefferson: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  115. [115]Property Values for Lake Township Released - Cook County Assessor's Office (press release, August 30, 2024)Official guide or FAQ · last checked Oct 1, 2026
  116. [116]Lake: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  117. [117]Property Values for Lake View Township Released - Cook County Assessor's Office (press release, July 5, 2024)Official guide or FAQ · last checked Oct 1, 2026
  118. [118]Lake View: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  119. [119]Lemont: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  120. [120]Property Values for Lemont Township Released - Cook County Assessor's Office (press release, August 19, 2026)Official guide or FAQ · last checked Oct 1, 2026
  121. [121]Leyden Township Property Values Released - Cook County Assessor's Office (press release, September 19, 2022)Official guide or FAQ · last checked Oct 1, 2026
  122. [122]Leyden Township: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  123. [123]Property Values for Leyden Township Released - Cook County Assessor's Office (press release, July 24, 2025)Official guide or FAQ · last checked Oct 1, 2026
  124. [124]Lyons Township: Residential - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  125. [125]Property Values for Lyons Township Released - Cook County Assessor's Office (press release, August 1, 2026)Official guide or FAQ · last checked Oct 1, 2026
  126. [126]Maine Township: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  127. [127]New Trier Township: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  128. [128]Niles Township Property Values Released - Cook County Assessor's Office (press release, November 4, 2022)Official guide or FAQ · last checked Oct 1, 2026
  129. [129]Niles Township: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  130. [130]Property Values for Niles Township Released - Cook County Assessor's Office (press release, November 2, 2025)Official guide or FAQ · last checked Oct 1, 2026
  131. [131]Property Values for North Chicago Township Released - Cook County Assessor's Office (press release, October 17, 2024)Official guide or FAQ · last checked Oct 1, 2026
  132. [132]North Chicago: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  133. [133]Northfield Township: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  134. [134]Norwood Park: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  135. [135]Oak Park: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  136. [136]Property Values for Oak Park Township Released - Cook County Assessor's Office (press release, May 20, 2026)Official guide or FAQ · last checked Oct 1, 2026
  137. [137]Property Values for Orland Township Released - Cook County Assessor's Office (press release, June 13, 2023)Official guide or FAQ · last checked Oct 1, 2026
  138. [138]Palatine Township Property Values Released - Cook County Assessor's Office (press release, August 24, 2022)Official guide or FAQ · last checked Oct 1, 2026
  139. [139]Palatine Township: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  140. [140]Property Values for Palatine Township Released - Cook County Assessor's Office (press release, September 10, 2025)Official guide or FAQ · last checked Oct 1, 2026
  141. [141]Palos: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  142. [142]Property Values for Palos Township Released - Cook County Assessor's Office (press release, June 5, 2026)Official guide or FAQ · last checked Oct 1, 2026
  143. [143]Proviso: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  144. [144]Property Values for Proviso Township Released - Cook County Assessor's Office (press release, October 9, 2023)Official guide or FAQ · last checked Oct 1, 2026
  145. [145]Assessor's Office | Rich TownshipOfficial guide or FAQ · last checked Oct 1, 2026
  146. [146]River Forest: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  147. [147]Property Values for River Forest Township Released - Cook County Assessor's Office (press release, April 24, 2026)Official guide or FAQ · last checked Oct 1, 2026
  148. [148]Riverside: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  149. [149]Rogers Park: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  150. [150]Schaumburg Township Property Values Released - Cook County Assessor's Office (press release, July 27, 2022)Official guide or FAQ · last checked Oct 1, 2026
  151. [151]Schaumburg Township: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  152. [152]Property Values for Schaumburg Township Released - Cook County Assessor's Office (press release, October 3, 2025)Official guide or FAQ · last checked Oct 1, 2026
  153. [153]Property Values for South Chicago Township Released - Cook County Assessor's Office (press release, October 31, 2024)Official guide or FAQ · last checked Oct 1, 2026
  154. [154]South Chicago: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  155. [155]Stickney: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  156. [156]Property Values for Stickney Township Released - Cook County Assessor's Office (press release, July 1, 2026)Official guide or FAQ · last checked Oct 1, 2026
  157. [157]Property Values for Thornton Township Released - Cook County Assessor's Office (press release, August 15, 2023)Official guide or FAQ · last checked Oct 1, 2026
  158. [158]West Chicago: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  159. [159]Wheeling Township Property Values Released - Cook County Assessor's Office (press release, October 12, 2022)Official guide or FAQ · last checked Oct 1, 2026
  160. [160]Wheeling Township: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  161. [161]Property Values for Wheeling Township Released - Cook County Assessor's Office (press release, August 19, 2025)Official guide or FAQ · last checked Oct 1, 2026
  162. [162]Worth: Residential Valuations - Cook County Assessor's OfficeOfficial guide or FAQ · last checked Oct 1, 2026
  163. [163]Worth Township Properties Reassessed - Cook County Assessor's Office (press release, June 25, 2020)Official guide or FAQ · last checked Oct 1, 2026
  164. 164.County open data: cook assessmentsRetrieved Sep 25, 2026; aggregated by us for the charts above.
  165. 165.County open data: cook parcelsRetrieved Sep 25, 2026; aggregated by us for the charts above.
  166. 166.County open data: cook parcelsRetrieved Sep 25, 2026; aggregated by us for the charts above.
  167. 167.County open data: cook parcelsRetrieved Sep 25, 2026; aggregated by us for the charts above.
  168. 168.County open data: appeal resultsAggregated by us for the appeal-results chart.
  169. 169.County open data: appeal resultsAggregated by us for the appeal-results chart.
  170. 170.U.S. Census Bureau, ACS 2020–2024 5-year estimates, table B25077: Median value (dollars), owner-occupied housing units — Cook County, Illinois
  171. 171.U.S. Census Bureau, ACS 2020–2024 5-year estimates, table B25103: Median real estate taxes paid, owner-occupied housing units — Cook County, Illinois
  172. 172.U.S. Census Bureau, ACS 2020–2024 5-year estimates, table B25003: Tenure (owner- and renter-occupied housing units) — Cook County, Illinois

Data credits: Census ACS (public domain) · Census county adjacency (public domain)

Not affiliated with Cook County or any government agency. Not legal advice. Not an appraisal.

Check my home free