Open data · CC BY 4.0
The national county property tax database.
Appeal windows, commercial assessment levels, value standards and boards for 55 US counties, searchable and exportable.
Windows of 30 days or fewer are highlighted. Rows with a linked county name open the full jurisdiction hub.
About the data
How often is the database verified?
Each county is checked against the assessor, the appeal board and the governing statute at least once a year, and again whenever a board publishes a new calendar. Every full jurisdiction record shows its last verified month.
Can I cite or reuse the data?
Yes. The database is published under Creative Commons Attribution 4.0. Cite ATALI ELECTRIC National County Property Tax Database with the month you accessed it.
Why do some counties show a fixed date instead of a number of days?
Some states set a calendar deadline (for example, California's July 2 to November 30 or September 15 window) rather than a count of days from the notice. The full rule is in the expanded row.
Is this the deadline for my parcel?
It is the general commercial rule. Mailing dates, township calendars and holiday rollovers change the actual last day, so confirm against your notice. ATALI ELECTRIC computes the parcel-level date inside the Deadline Tracker.
Never miss a statutory window again.
The Deadline Tracker turns these rules into parcel-level due dates, reminders and hearing calendars across every county you file in.