Property Tax Assessment Appeal · California
Appeal your assessment
in California.
Proposition 13 caps how fast your base-year value can grow, so most California homeowners appeal in one of two situations: the market value of the home has dropped below the assessed value (a "decline in value" or Prop 8 appeal), or a reassessment event — like a purchase or new construction — set the base-year value too high. You file an Application for Changed Assessment with your county’s Assessment Appeals Board and present evidence of market value as of the January 1 lien date.
The regular filing window runs July 2 through either September 15 or November 30, depending on your county. Check which deadline your county uses.
Because Prop 13 keeps long-held assessments low, the homeowners with the strongest cases are usually recent buyers and owners in markets that have cooled since purchase. Decline-in-value reductions are temporary — the assessor can restore value as the market recovers — but the savings while they last are real.
The evidence
Boards act on value,
not frustration.
However California labels the process, the case underneath is identical: show what your home was actually worth on the assessment date. A licensed, USPAP-compliant appraisal — comparable sales, documented adjustments, a signed opinion of value — is that showing. Start with the $5 check to see if the numbers are on your side before you spend real money.
- Valued as of your assessment date — not today
- Comparable sales with adjustments and citations
- Signed by a state-licensed CA appraiser
- Phone walkthrough — no stranger in your home
- Delivered in 48–72 hours, rush available
California counties
California questions
A request to temporarily lower your assessment because the market value of your home on January 1 fell below your Prop 13 factored base-year value. Evidence of market value — like a licensed appraisal as of the lien date — is the core of the case.
The regular window opens July 2 and closes September 15 or November 30 depending on the county. Supplemental and escape assessments have their own 60-day windows from the notice date.
We’re not an AVM, a computer model, or a real-estate agent estimate. Every report is prepared under the Uniform Standards of Professional Appraisal Practice (USPAP) and signed by a licensed appraiser in your state — the same qualification required for mortgage appraisals.