| County | Deadline | Days left | Data |
|---|---|---|---|
| Los Angeles County, CA | November 30 | 47d | |
| San Diego County, CA | November 30 | 47d | |
| Orange County, CA | November 30 | 47d | |
| Sacramento County, CA | November 30 | 47d | |
| Multnomah County, OR | December 31 | 78d | |
| Clark County, NV | January 15 | 93d | |
| Franklin County, OH | March 31 | 168d | |
| Cuyahoga County, OH | March 31 | 168d | |
| Allegheny County, PA | March 31 | 168d | live data |
| Hennepin County, MN | April 30 | 198d | |
| Harris County, TX | May 15 | 213d | non-disclosure |
| Dallas County, TX | May 15 | 213d | non-disclosure |
| Tarrant County, TX | May 15 | 213d | non-disclosure |
| Travis County, TX | May 15 | 213d | non-disclosure |
| Bexar County, TX | May 15 | 213d | non-disclosure |
| Collin County, TX | May 15 | 213d | non-disclosure |
| Denton County, TX | May 15 | 213d | non-disclosure |
| Wayne County, MI | May 31 | 229d | |
| Oakland County, MI | May 31 | 229d | |
| Marion County, IN | June 15 | 244d | |
| King County, WA | July 1 | 260d | live data |
| Clark County, WA | July 1 | 260d | |
| Davidson County, TN | August 1 | 291d | |
| Shelby County, TN | May 1 – June 30 | 291d | |
| Riverside County, CA | September 15 | 336d | |
| Santa Clara County, CA | September 15 | 336d | |
| Alameda County, CA | September 15 | 336d | |
| Salt Lake County, UT | September 15 | 336d | non-disclosure |
| Philadelphia County, PA | first Monday in October | 358d | live data |
These counties have no single calendar date — the clock starts when your value/assessment notice is mailed. We show the rule; confirm your exact date on the notice.
| County | Rule | When | Data |
|---|---|---|---|
| Cook County, IL | 30 days after your township opens | by notice | live data |
| Miami-Dade County, FL | 25 days after your TRIM notice | by notice | |
| Broward County, FL | 25 days after your TRIM notice | by notice | |
| Palm Beach County, FL | 25 days after your TRIM notice | by notice | |
| Hillsborough County, FL | 25 days after your TRIM notice | by notice | |
| Duval County, FL | 25 days after your TRIM notice | by notice | |
| Maricopa County, AZ | 60 days after your Notice of Value | by notice | live data |
| Pima County, AZ | 60 days after your Notice of Value | by notice | |
| Fulton County, GA | 45 days after your Annual Notice of Assessment | by notice | non-disclosure |
| Jefferson County, KY | during the 13-day open-inspection period | by notice | |
| Mecklenburg County, NC | before the county Board of Equalization & Review adjourns | by notice | |
| Wake County, NC | before the county Board of Equalization & Review adjourns | by notice | |
| Suffolk County, NY | Grievance Day | by notice |
live data = we run a per-parcel over-assessment check on this county's public roll. non-disclosure = the state doesn't publish sale prices, so over-assessment is argued from comparable assessed values instead. All 67 Pennsylvania counties →