Cook County property tax
appeal deadlines.
We have not verified any township's 2026 filing deadline against the Cook County Assessor's published calendar, so this page shows none. Every township below is marked pending — we don't guess. Confirm your exact deadline with the county before filing.
Verify your deadline before you file.
We have not verified this township's filing deadline against the county's published calendar, so we are not showing one. Cook County publishes and revises appeal dates through the year, and they vary by township. Confirm your exact filing deadline with the official county source below before you file.
- Cook County Assessor — Assessment & Appeal CalendarThe official filing deadline (last file date) for each township. Updated through the year as townships open.
- Cook County Board of Review — AppealsThe second-level appeal window, which opens separately from the Assessor's and has its own deadline per township.
- Cook County Assessor — Property SearchLook up your PIN, township, and current assessment by address.
Not sure which window applies to you? Request a review and we'll help you confirm it — email support@overtaxed-il.com or call (847) 461-3189. We never file anything without your go-ahead.
Confirm your deadline with the county.
This calendar does not determine your property's eligibility or enroll you in reminders. Check the official Cook County Assessor calendar before filing.
Township deadlines at a glance.
Grouped by the Assessor's official 2026 status. “Pending official date” means we do not have a freshly verified official date here — confirm yours before filing.
- BerwynPending official date
- BloomPending official date
- BremenPending official date
- CalumetPending official date
- CiceroPending official date
- LemontPending official date
- LyonsPending official date
- Oak ParkPending official date
- OrlandPending official date
- PalosPending official date
- ProvisoPending official date
- RichPending official date
- River ForestPending official date
- RiversidePending official date
- StickneyPending official date
- ThorntonPending official date
- WorthPending official date
- BarringtonPending official date
- Elk GrovePending official date
- EvanstonPending official date
- HanoverPending official date
- LeydenPending official date
- MainePending official date
- New TrierPending official date
- NilesPending official date
- NorthfieldPending official date
- Norwood ParkPending official date
- PalatinePending official date
- SchaumburgPending official date
- WheelingPending official date
- Hyde ParkPending official date
- JeffersonPending official date
- LakePending official date
- Lake ViewPending official date
- North ChicagoPending official date
- Rogers ParkPending official date
- South ChicagoPending official date
- West ChicagoPending official date
Official 2026 township deadlines.
Dates shown are the Cook County Assessor's official 2026 Last File Date. Townships marked “Pending official date” do not have a freshly verified official date here. We do not estimate missing dates or infer whether the county has posted them. Confirm any date on the official Cook County Assessor calendar before filing.
| Township | Status | Official 2026 deadline | Days | Cycle | |
|---|---|---|---|---|---|
| Barrington | Pending date | Pending official date | — | 2027 | → |
| Berwyn | Pending date | Pending official date | — | 2026 | → |
| Bloom | Pending date | Pending official date | — | 2026 | → |
| Bremen | Pending date | Pending official date | — | 2026 | → |
| Calumet | Pending date | Pending official date | — | 2026 | → |
| Cicero | Pending date | Pending official date | — | 2026 | → |
| Elk Grove | Pending date | Pending official date | — | 2027 | → |
| Evanston | Pending date | Pending official date | — | 2027 | → |
| Hanover | Pending date | Pending official date | — | 2027 | → |
| Hyde Park | Pending date | Pending official date | — | 2028 | → |
| Jefferson | Pending date | Pending official date | — | 2028 | → |
| Lake | Pending date | Pending official date | — | 2028 | → |
| Lake View | Pending date | Pending official date | — | 2028 | → |
| Lemont | Pending date | Pending official date | — | 2026 | → |
| Leyden | Pending date | Pending official date | — | 2027 | → |
| Lyons | Pending date | Pending official date | — | 2026 | → |
| Maine | Pending date | Pending official date | — | 2027 | → |
| New Trier | Pending date | Pending official date | — | 2027 | → |
| Niles | Pending date | Pending official date | — | 2027 | → |
| North Chicago | Pending date | Pending official date | — | 2028 | → |
| Northfield | Pending date | Pending official date | — | 2027 | → |
| Norwood Park | Pending date | Pending official date | — | 2027 | → |
| Oak Park | Pending date | Pending official date | — | 2026 | → |
| Orland | Pending date | Pending official date | — | 2026 | → |
| Palatine | Pending date | Pending official date | — | 2027 | → |
| Palos | Pending date | Pending official date | — | 2026 | → |
| Proviso | Pending date | Pending official date | — | 2026 | → |
| Rich | Pending date | Pending official date | — | 2026 | → |
| River Forest | Pending date | Pending official date | — | 2026 | → |
| Riverside | Pending date | Pending official date | — | 2026 | → |
| Rogers Park | Pending date | Pending official date | — | 2028 | → |
| Schaumburg | Pending date | Pending official date | — | 2027 | → |
| South Chicago | Pending date | Pending official date | — | 2028 | → |
| Stickney | Pending date | Pending official date | — | 2026 | → |
| Thornton | Pending date | Pending official date | — | 2026 | → |
| West Chicago | Pending date | Pending official date | — | 2028 | → |
| Wheeling | Pending date | Pending official date | — | 2027 | → |
| Worth | Pending date | Pending official date | — | 2026 | → |
Check if your assessment is too high.
Knowing the deadline is half of it. The other half is knowing whether your assessed value is actually out of line with comparable properties. Free, takes 30 seconds, no signup.