BOE-305-AH (Assessment Appeal Application)
BOE-305-AH is the state-prescribed form Californians use to formally appeal a property tax assessment. Filing it with your county's Assessment Appeals Board opens a formal case where you argue that your property's assessed value exceeds its market value. In San Francisco it's also called the "Application for Changed Assessment." It's the document that officially starts your appeal.
What the form does
The "BOE" prefix means the form is standardized statewide by the California State Board of Equalization, so every county uses the same core application (BOE-305-AH sample). On it, you identify the property, state the assessor's value, and state your opinion of the property's value — the gap between those two numbers is what your appeal is about. You'll also indicate the type of assessment you're contesting (regular, supplemental, escape, etc.).
When and how to file
The form must be filed during your county's appeal window, which is a hard deadline. In counties that mail value notices to all owners — including San Francisco — the regular window runs July 2 through September 15; other counties run through November 30 (BOE Publication 30). Most counties charge a processing fee per application. Filing the form is only step one: you'll later present your evidence — typically comparable sales near the January 1 valuation date — at a hearing before the appeals board.
How it affects your appeal
Getting BOE-305-AH right matters. The "opinion of value" you write down frames your entire case, and in some counties the gap between that figure and the assessed value determines whether a fee applies. Filing the wrong appeal type, or missing the deadline, can sink an otherwise strong case. Because it's the formal trigger, the form is what preserves your right to a hearing — so even if you also pursue an informal review with the assessor, file the application by the deadline to protect your appeal.
BOE-305-AH is California-specific. Other states use their own application or "protest" forms for the equivalent step. For the official version, see the BOE-305-AH sample form.
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