When is the Leyden Township property tax appeal window?

The Leyden Township Board of Review appeal window runs February 3, 2026 through March 3, 2026. You must file before the closing date — late appeals are not accepted.

How do I file a Leyden property tax appeal online?

File online at the Cook County Board of Review portal (cookcountyboardofreview.com). Create an account, select Leyden Township, and upload your evidence. The Board of Review publishes a step-by-step portal guide for property owners at cookcountyboardofreview.com/portal-guide-property-owners. TTM's $49 data report provides comparable property data and estimated assessment differences that you may use as supporting information.

How do I know if my Leyden home is over-assessed?

Your home is over-assessed for uniformity purposes if its assessed value per square foot is higher than comparable properties in the same Cook County Assessor neighborhood and property class. TTM compares your property against your neighbors using official CCAO open data — the free lookup at taxedtoomuch.com shows your position in seconds.

How much can I save by appealing my Leyden property taxes?

A successful appeal reduces your assessed value, which lowers your tax bill each year until the next reassessment. How much you might save depends on how far above neighbors you are assessed per square foot. TTM's free lookup compares your home to similar properties in the same Cook County Assessor neighborhood so you can see your position before you decide whether to file.

Do I need an attorney to appeal my Leyden property taxes?

The Board of Review allows homeowners to file directly. Some choose to file on their own; others work with a tax attorney or consultant. TTM provides the same comparable property data and analysis regardless of how you choose to proceed — whether you file yourself or share the report with a professional. TTM is not a law firm, does not file appeals on your behalf, and does not provide legal advice. For questions about your specific situation, consult a qualified tax attorney or professional.

What is a Cook County uniformity appeal?

A uniformity appeal argues that your property is assessed at a higher rate per square foot than comparable properties in the same neighborhood and class — a legal basis for reduction under Illinois law (35 ILCS 200/9-145). Unlike a market value appeal, you don't need an independent appraisal. You need evidence that similar nearby properties are assessed lower than yours. The Cook County Board of Review accepts uniformity appeals online during each township's annual filing window at no cost to the homeowner.

Appeal Deadlines/Leyden Township

Cook County · North/Northwest

Leyden Township Property Tax Appeal

Leyden Township covers Franklin Park, Rosemont, and Schiller Park. The proximity to O'Hare and major industrial corridors creates a diverse property mix where residential assessment accuracy varies considerably.

TTMis a Cook County property tax data tool that compares your home's assessed value per square foot to similar properties in your CCAO neighborhood using official assessor data. The free lookup shows whether your assessment may be higher than comparable properties; a $49 data report gives you comparable properties, estimated assessment differences, an AI-generated data summary, and general filing information — informational data you can review before deciding whether to file at the Board of Review yourself, or to share with your attorney. TTM does not file appeals on your behalf.

Board of Review appeal window

February 3, 2026 — March 3, 2026

Check my property — free File appeal at Board of Review ↗

Uniformity appeals in Leyden

Illinois law lets you ask the Board of Review for relief when your home is assessed higher per square foot than truly comparable properties in the same Cook County Assessor neighborhood and property class—without needing your own appraisal for a uniformity argument.

TTM uses official CCAO open data to compare your building assessment per square foot to neighbors like yours. Start with the free lookup; if you want comparable parcel tables and a written summary for your own filing, the data report is a one-time $49. Read how uniformity appeals work.

How to file a Leyden Township appeal

1
Check your property — free
Enter your address or PIN at TTM to see if you're over-assessed compared to neighbors.
2
Get your data report — $49
Get your full data report: comparable properties, estimated assessment differences, AI-generated data summary, and general filing information. Informational only.
3
File online at the Board of Review
Go to cookcountyboardofreview.com ↗ — create an account, select Leyden Township, upload your report as evidence, and submit. Takes about 15 minutes. You can file directly or share the report with a tax professional. New to the portal? See the Board of Review's step-by-step filing guide ↗.
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Optional: also appeal at the township assessor
Leyden Township has its own assessor office at leydenassessor.com ↗. You can file at both the township assessor and the Board of Review — the BOR is typically more impactful.

Frequently asked questions — Leyden Township property tax appeals

When is the Leyden Township property tax appeal window?: The Leyden Township Board of Review appeal window runs February 3, 2026 through March 3, 2026. You must file before the closing date — late appeals are not accepted.
How do I file a Leyden property tax appeal online?: File online at the Cook County Board of Review portal (cookcountyboardofreview.com). Create an account, select Leyden Township, and upload your evidence. The Board of Review publishes a step-by-step portal guide for property owners at cookcountyboardofreview.com/portal-guide-property-owners. TTM's $49 data report provides comparable property data and estimated assessment differences that you may use as supporting information.
How do I know if my Leyden home is over-assessed?: Your home is over-assessed for uniformity purposes if its assessed value per square foot is higher than comparable properties in the same Cook County Assessor neighborhood and property class. TTM compares your property against your neighbors using official CCAO open data — the free lookup at taxedtoomuch.com shows your position in seconds.
How much can I save by appealing my Leyden property taxes?: A successful appeal reduces your assessed value, which lowers your tax bill each year until the next reassessment. How much you might save depends on how far above neighbors you are assessed per square foot. TTM's free lookup compares your home to similar properties in the same Cook County Assessor neighborhood so you can see your position before you decide whether to file.
Do I need an attorney to appeal my Leyden property taxes?: The Board of Review allows homeowners to file directly. Some choose to file on their own; others work with a tax attorney or consultant. TTM provides the same comparable property data and analysis regardless of how you choose to proceed — whether you file yourself or share the report with a professional. TTM is not a law firm, does not file appeals on your behalf, and does not provide legal advice. For questions about your specific situation, consult a qualified tax attorney or professional.
What is a Cook County uniformity appeal?: A uniformity appeal argues that your property is assessed at a higher rate per square foot than comparable properties in the same neighborhood and class — a legal basis for reduction under Illinois law (35 ILCS 200/9-145). Unlike a market value appeal, you don't need an independent appraisal. You need evidence that similar nearby properties are assessed lower than yours. The Cook County Board of Review accepts uniformity appeals online during each township's annual filing window at no cost to the homeowner.

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