Cook County Tax Appeal Agencies

Cook County Assessor’s Office (CCAO)

Headed by an elected official, this agency re-assesses property values every three years on a rotating basis between townships located in the City of Chicago, North & Northwest Suburbs, and South & Southwest suburbs.  The agency can — by hearing and deciding on appeals — adjust assessments and correct for factual errors.  Appeals are  accepted for approximately 20 business days after reassessment notices are mailed to taxpayers, but also can be submitted in the second or third year of a “triennial” cycle.  The CCAO also is granted powers to act on taxpayer applications for refunds (based on eligibility and evidence) for up to three years.

  • Assessment notices mailed on triennial schedule by township
  • Assessment appeals accepted until township deadlines
  • First Appeal Decisions are made
  • Re-reviews submitted and considered (optional)
  • Assessment Appeal Decisions are certified
  • Prior years’ Certificate of Error (CofE) for Homeowner Exemption processing
  • Prior years’ certificate of Error appeals for non-homeowner Exemption errors
  • CofE Applications considered on a rolling deadline basis
  • When applicable, non-homeowner exemption Certificate of Errors sent to Board of Review for  subsequent review
  • Omitted assessment notices issued


Cook County Board of Review (CCBR)

Three elected commissioners head this agency which is empowered to hear and act on appeals for changes to assessments, make corrections of factual errors, order corrections of appeal decisions made by the Assessor, and review and typically approve decisions made by the Assessor on non-homeowner Exemption Certificate of Errors. Decisions normally are made before second installment tax bills (typically Jul 1) are issued so that tax relief may be reflected on those bills.  After decisions are complete, taxpayers may further challenge decisions through either the State Property Tax Appeal Board (PTAB), which could take in excess of two years before finalizing a decision and/or refund, or through the Circuit Court.


  • Complaint filed with or without evidence
  • Evidence submission, if not submitted with the complaint
  • Appeals heard and decided on a schedule of township deadlines
  • First Appeal Decision letters issued
  • Re-reviews submitted and considered (optional)
  • Final Appeal Decisions Certified
  • Certificate of Error approval per Assessor’s request
  • If appeals made to PTAB, the CCBR may appear at hearings
  • Processes omitted assessment complaints
  • Processes undervaluation complaints

What Every Property Owner Should Know

About the Real Estate Tax Appeals Process

  • Appeals normally are processed through 2 county agencies – the Cook County Assessor’s Office and the Cook County Board of Review.
  • You are not required to file first at the Assessor’s office to seek tax relief at the Board of Review.  However, you must at least file an appeal at the Board of Review to seek tax relief at the State Property Tax Appeal Board (PTAB).
  • You may file with any appeal agency as often as you feel necessary to achieve a fair tax adjustment on any given year, not just in the first triennial reassessment year.
  • Appeal reviewers may take as long as 3 to 5 months to finalize a decision on your tax complaint, but your tax savings can last as long as 3 years.
  • All tax savings granted by the Assessor and Board of Review will appear on your second installment tax bill.  PTAB reductions can be granted only as refunds.
  • There are 38 townships in Cook County with 2 specific deadlines for each — initial filing deadlines and re-review deadlines. Because we must monitor and meet 76 deadlines within 6 months, it is impossible to contact each taxpayer while cases are actively undergoing the review process.
  • When appealing property taxes, patience is a must! You will be informed, once your case is finally decided.

Important Information for Clients