Appealing Your Property Tax Assessment in California

A first step is often to discuss the assessment informally with the assessor's staff. The formal appeal is an Assessment Appeal Application filed with the clerk of the county board of supervisors (sitting as a local board of equalization) or the assessment appeals board during the regular filing period, July 2 through September 15, or through November 30 in counties where the assessor does not mail assessment notices to all secured-roll taxpayers by August 1 (for 2026: July 2 to September 15, 2026, or November 30, 2026). Supplemental and escape assessments must be appealed within 60 days after the notice is mailed. For an owner-occupied single-family principal residence, the assessor has the burden of proving the value is correct.

Secured property tax bills are mailed by November 1 and paid in two equal installments: the first is due November 1 and delinquent after December 10; the second is due February 1 and delinquent after April 10. Late payment adds a 10% penalty. Unsecured taxes are due January 1 and delinquent August 31.