Assessor vs. Board of Review vs. PTAB: where to appeal your Cook County property taxes

Cook County gives homeowners three separate places to challenge a property tax assessment. They're not interchangeable — each has its own timing, process, and odds. Here's the plain-English version.

The Cook County Assessor

This is where every assessment starts and where your first appeal goes. The Assessor's office sets your home's assessed value, and each township gets its own filing window each year. Filing is free and done online. Strong comparable evidence — similar nearby homes assessed lower per square foot than yours — is what wins here.

The Cook County Board of Review

Think of this as your second, independent shot. The Board opens its own township windows after the Assessor finishes. You can file here even if you already filed with the Assessor, and many homeowners do both in the same year. Same idea: free, online, and driven by comparables.

PTAB (the state level)

The Property Tax Appeal Board is Illinois's state-level review, based in Springfield. It's the slowest and most formal option, usually used after a Board of Review decision you disagree with. Most homeowners never need to go this far.

Which one should you file with?

The short answer: file at every level you're eligible for, starting with the Assessor. Each filing is free, each is a fresh look, and a win at any level lowers your bill. The only real cost is your time — and a well-prepared evidence packet.

The evidence is the same everywhere

Whichever office you file with, the core argument doesn't change: my home is assessed higher per square foot than similar homes in my neighborhood. Our $79 kit builds that argument for you from public county records, with the comparables table, recent sales, and a worksheet that tells you exactly what to type into each filing form.

NeighborComp is a private company and is not affiliated with the Cook County Assessor, Board of Review, or any government office. We do not provide legal advice and do not file appeals on your behalf. Savings shown are estimates, not guarantees.