Rob Hartley
Founder, AppealDesk · Published June 24, 2026
Property Tax Appeal Deadline Guide by County (2026)
Updated June 2026 · 10 min read
Every county has a different property tax appeal deadline — and missing it forfeits your right to appeal for the year. This guide covers the appeal deadlines for the 30 most-populated U.S. counties, plus a link to every county's dedicated appeal page.
Property Tax Appeal Deadlines: Top 30 Counties by Population
Deadlines vary by state and county. Dates below are for 2026. Always verify your deadline on your assessment notice or at your county assessor's website.
| County | 2026 Deadline | Type | Notes |
|---|---|---|---|
| Los Angeles County, CA | Sep 15 or Nov 30 | Variable | Window opens Jul 2 |
| Cook County, IL | Township-specific (spring–fall) | Variable | Board of Review open annually |
| Harris County, TX | May 15 or 30 days from notice | Rolling | Whichever is later |
| Maricopa County, AZ | Apr 21 (2026) | Fixed | 60 days from NOV mailing |
| San Diego County, CA | Sep 15 | Fixed | Window opens Jul 2 |
| Orange County, CA | Sep 15 | Fixed | Window opens Jul 2 |
| Miami-Dade County, FL | 25 days from TRIM (~early Sep) | Rolling | TRIM mailed mid-Aug |
| Dallas County, TX | May 15 or 30 days from notice | Rolling | Whichever is later |
| Riverside County, CA | Sep 15 | Fixed | Window opens Jul 2 |
| San Bernardino County, CA | Sep 15 | Fixed | Window opens Jul 2 |
| Tarrant County, TX | May 15 or 30 days from notice | Rolling | Whichever is later |
| Broward County, FL | 25 days from TRIM (~early Sep) | Rolling | TRIM mailed mid-Aug |
| Santa Clara County, CA | Sep 15 | Fixed | Window opens Jul 2 |
| Bexar County, TX | May 15 or 30 days from notice | Rolling | Whichever is later |
| Wayne County, MI | Mar 9 (BOR) | Fixed | Must attend local BOR |
| Alameda County, CA | Sep 15 | Fixed | Window opens Jul 2 |
| Sacramento County, CA | Sep 15 | Fixed | Window opens Jul 2 |
| Contra Costa County, CA | Sep 15 | Fixed | Window opens Jul 2 |
| Palm Beach County, FL | 25 days from TRIM (~early Sep) | Rolling | TRIM mailed mid-Aug |
| Cuyahoga County, OH | Mar 31 | Fixed | Jan 1 – Mar 31 window |
| Nassau County, NY | Mar 1 | Fixed | Assessed value grievance |
| Suffolk County, NY | May 21 (2026) | Fixed | 4th Tue in May |
| Middlesex County, NJ | Apr 1 | Fixed | Standard NJ deadline |
| Bergen County, NJ | Apr 1 | Fixed | Standard NJ deadline |
| Gwinnett County, GA | 45 days from notice (~Aug) | Rolling | Notices mailed spring/summer |
| Fulton County, GA | 45 days from notice (~Oct) | Rolling | Notices mailed August |
| King County, WA | Jul 1 or 60 days from notice | Rolling | Whichever is later |
| Clark County, NV | Jan 15 | Fixed | Earliest fixed deadline |
| Travis County, TX | May 15 or 30 days from notice | Rolling | Whichever is later |
| Collin County, TX | May 15 or 30 days from notice | Rolling | Whichever is later |
Check Your County Deadline
Enter your address to see your specific county's appeal deadline and whether your home is over-assessed.
Understanding the Three Deadline Types
Fixed deadlines are calendar-based dates that apply to everyone regardless of when you received your notice. Examples include New Jersey (April 1), Ohio (March 31), and Nevada (January 15). If you miss the date, you miss the window.
Rolling deadlines count from the date your assessment notice was mailed. Texas gives you 30 days from your notice (or May 15, whichever is later). Georgia gives 45 days. Florida gives 25 days from your TRIM notice. Check the date on your notice to calculate your deadline.
Variable deadlines differ within the state by county or type of property. California deadlines vary by county (September 15 in most; November 30 in Los Angeles). Illinois deadlines vary by township within Cook County. New York varies by whether you are in NYC or upstate.
County-Specific Appeal Guides
For the counties with the most appeal activity, we have dedicated step-by-step guides:
- Gwinnett County Property Tax Appeal Guide
- Fulton County Property Tax Appeal Guide
- Cook County Property Tax Appeal Guide
- Harris County Property Tax Protest Guide
- Full Deadline Guide: All 50 States
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