Tax appeals
Cook County Reassessment 2026: Township Deadlines
Cook County’s 2026 reassessment cycle covers the south and west suburbs. The official calendar lists township-specific dates and separate appeal stages.
Updated September 10, 2026
On this page
Check your property’s township and current calendar entry before relying on any general deadline or ordering evidence.
Find your township and appeal stage
Use the Assessor’s current calendar to find the relevant last-file date. The Assessor and Board of Review have separate windows; do not treat one date as covering both.
Read the notice and property record
Compare the property characteristics and value with the records you have. Keep a copy of the notice and identify the specific issue you want reviewed.
Confirm the evidence and filing rules
Check the current instructions for the stage you are using. Ask whether an appraisal is necessary or useful and what effective date is required. A paid report does not file an appeal for you.
Keep expectations tied to the decision
An assessment change does not guarantee a fixed tax savings amount. Tax shares and other components can change. Check the decision, bill and next notice rather than assuming a three-year savings promise.
Questions people ask
Can I appeal outside a reassessment year?
The official 2026 calendar also lists appeal opportunities for townships not undergoing scheduled reassessment. Check your township and stage rather than assuming a window is open.
What is my exact deadline?
Use the official calendar below and confirm with the relevant office. Township dates can differ and should be rechecked before filing.
Sources
Sources checked September 10, 2026. Confirm the requirements for your specific assignment with your recipient or advisor.
