When is the property tax appeal deadline in Los Angeles County?

Los Angeles County uses the November 30 closing date. The regular filing period under Cal. Rev. & Tax. Code §1603 opens July 2 and, because the L.A. County Assessor does not send an assessed-value notice to all secured-roll owners by August 1, the deadline extends to November 30 rather than September 15.

In Los Angeles County you file the BOE-305-AH Assessment Appeal Application with the Los Angeles County Assessment Appeals Board / Clerk of the Board, not with the assessor. The county also runs a decline-in-value (Proposition 8) path: if your market value on the January 1 lien date is below your factored base year value under Cal. Rev. & Tax. Code §51, you can request an informal review, but that request does not extend the November 30 formal-appeal deadline.

Key reminders for L.A. County owners:

• Confirm the date annually — November 30 applies as long as the August 1 universal-notice condition is unmet, which is the county's longstanding practice, but verify on the Clerk of the Board's published filing period each year.
• Pay the tax bill on time regardless of a pending appeal to avoid penalties.
• Supplemental assessments (after a purchase or new construction) carry their own 60-day appeal window under Cal. Rev. & Tax. Code §75.31, separate from the November 30 regular period.

The state BOE assessment appeals overview confirms the July 2 / September 15 / November 30 framework that L.A. County follows.