///CALIFORNIA · COUNTY GUIDE
The 2026 deadline to appeal a San Bernardino County property tax assessment is November 30, 2026. The filing window runs from July 2, 2026 to November 30, 2026.
For regular assessment appeals, the filing period is July 2 through November 30 for San Bernardino County for the 2026 assessment year. Supplemental and escape assessments have a separate 60-day-from-mailing rule, and calamity assessments have a six-month-from-mailing rule.
| 2026 appeal deadline | November 30, 2026 |
|---|---|
| Filing window opens | July 2, 2026 |
| File with | San Bernardino County Clerk of the Board / Assessment Appeals Board |
| After a successful appeal | A Proposition 8 decline-in-value reduction is reviewed every year and holds while the market supports it. |
| Can a board raise the value? | Yes — see below (Cal. Rev. & Tax. Code §1610.8) |
| Deadline source | Plan ahead when mailing deadline-sensitive documents to the county |
| Last verified | August 16, 2026 |
The 2026 deadline is November 30, 2026. The window opens July 2, 2026. For regular assessment appeals, the filing period is July 2 through November 30 for San Bernardino County for the 2026 assessment year. Supplemental and escape assessments have a separate 60-day-from-mailing rule, and calamity assessments have a six-month-from-mailing rule.
Appeals are filed with the San Bernardino County Clerk of the Board / Assessment Appeals Board.
California assessments start from a Proposition 13 base-year value that rises about 2% a year. Proposition 8 requires the assessor to enroll the lower of that factored base value or the property's current market value, so when the market falls below the roll, a decline-in-value appeal applies. Several counties offer an informal review with the assessor first; formal appeals go to the county Assessment Appeals Board, and a Prop 8 reduction is reviewed every year, holding while the market supports it.
It's possible — a California Assessment Appeals Board equalizes the roll by reducing or increasing an assessment (Cal. Rev. & Tax. Code §1610.8), and the Proposition 13 ceiling protects decline-in-value appeals, not base-year disputes. That's why we check for that exposure before filing: we don't file when we see it, and if it surfaces after filing we withdraw.
Enter your address and we'll check San Bernardino County's own records at no cost. If there's no case, we'll tell you that too.
Serving greater Los Angeles.
California property tax appeals. Any estimate is based on county assessment data and public records and is not a guarantee of any outcome. Representation and fee terms are provided in writing before any filing. Deadline information reflects published county materials as of the date shown above — verify with the San Bernardino County Clerk of the Board / Assessment Appeals Board before relying on it.