How to Appeal Your Property Tax in Santa Clara County
If your Santa Clara County home is assessed for more than it's worth, you can reduce your property tax bill. There are two paths: a free informal review (deadline: August 1) and a formal appeal (deadline: September 15, $290 fee). Most homeowners should start with the free path.
Two ways to appeal your property tax
Santa Clara County offers two paths: a free informal review through the Office of the Assessor, County of Santa Clara, or a formal appeal through the Santa Clara County Assessment Appeals Board with a $290 nonrefundable filing fee. The Assessor proactively reduced over 17,000 residential assessments in 2023 — the free informal review is your best first step.
Track 1: Free Informal Review (Prop 8)
Through the Office of the Assessor, County of Santa Clara
The informal Prop 8 review is a free request you submit directly to the Office of the Assessor, County of Santa Clara — no hearing, no fee, and no risk that your assessment will increase. You provide evidence that your property's market value has declined below its assessed value, and the Assessor reviews it. If they agree, your assessed value is reduced for the current tax year. Results are typically communicated by mid-August, giving you time to file a formal appeal by September 15 if you're unsatisfied with the outcome.
- Free to file — no fee
- No hearing required — the Assessor reviews your evidence directly
- No risk of increase — the Assessor can only reduce or confirm your value
- Submit via the Assessor's online tool, phone ((408) 299-5500), email, or mail
Submit by August 1
The earlier you submit, the sooner you'll get a response. Results typically arrive by mid-August — early enough to file a formal appeal by September 15 if needed.
Track 2: Formal Appeal (BOE-305-AH)
Through the Santa Clara County Assessment Appeals Board
The formal appeal is filed with the Santa Clara County Assessment Appeals Board using the BOE-305-AH form. It requires a $290 nonrefundable filing fee per parcel and results in a scheduled hearing — either in-person or virtual (zoom webinar) — where you present evidence to support your requested value. The Board can reduce, confirm, or in rare cases increase your assessed value, so come prepared with strong comparable sales data. Hearings may be scheduled 6 to 24 months after filing.
- Filing window: July 2 – September 15 each year. If September 15 falls on a weekend, the deadline extends to the next business day.
- $290 nonrefundable filing fee per parcel (effective June 1, 2026).
- Download the form from the forms page — there is no online submission portal. Print, complete, and mail to County of Santa Clara – Assessment Appeals Board, 70 W. Hedding Street, 10th Floor, East Wing, San Jose, CA 95110
- Request a Value Hearing Officer (Item #9) for a less formal residential hearing
File both tracks to protect your rights
File both the free informal review (by August 1) and the formal appeal (by September 15). If the informal review reduces your assessment, you can withdraw the formal appeal. But if you skip the formal filing and the informal review doesn't go your way, you'll have no recourse until next year.
How to file — step by step
The Santa Clara County appeal process has two tracks that work together: a free informal review and a formal appeal. Here's how to use both to maximize your chances of a reduction.
Check if you qualify
Look up your property's assessed value on the Assessor's website and compare it to recent comparable sales in your neighborhood — if your market value is lower, you likely qualify for a reduction.
Overassessed does this for you — enter your address and we'll pull your assessment and run the comparison.
Gather comparable sales
Find 3–5 comparable homes that sold on or before March 31 of the current year, ideally nearby properties with similar size, age, and condition. The Assessor's Appraisal & Comparable Sales Look-Up tool is a free starting point.
The Overassessed Filing Guide includes selected comps with professional-grade adjustments, ready to submit.
File the informal review
Submit a free decline-in-value request to the Office of the Assessor, County of Santa Clara by August 1 — this costs nothing and the Assessor can only reduce or confirm your value.
File the formal appeal (BOE-305-AH) as backup
File the formal BOE-305-AH application with the Santa Clara County Assessment Appeals Board by September 15 as a backup, even if you're still waiting for informal results — the $290 fee is nonrefundable but preserves your right to a hearing.
Prepare for your hearing
When your hearing notice arrives (typically 6–24 months later), prepare your evidence package and return the Appeal Response Form at least 21 days before your hearing date. Bring 6 copies for AAB hearings or 4 copies for VHO hearings.
Our Filing Guide gives you copy-paste values for every field on the county form, plus a deadline tracker.
Check if you qualify →What evidence do I need?
The strongest evidence for a residential property tax appeal is comparable sales — recent sales of similar homes near your property. Under California law, only sales that closed escrow on or before March 31 (90 days after the January 1 lien date) can be considered.
The Santa Clara County Assessor provides an Appraisal and Comparable Sales Look-Up tool that lets you view the market data used in your assessment — start there. Aim for 3–5 comps with similar square footage, lot size, bedrooms, and condition, ideally within a mile of your home.
“Similar” means comparable in:
- Square footage and lot size
- Bedrooms and bathrooms
- Condition and age
- Proximity to your home
Do not attach evidence to your application
Evidence is presented at the hearing, not with the BOE-305-AH application. Bring 6 copies for Santa Clara County Assessment Appeals Board hearings or 4 copies for Value Hearing Officer hearings.
Why adjustments matter
If a comp is smaller or has fewer bedrooms than your home, the assessor will adjust the sale price upward to account for the difference. You want comps that are genuinely comparable after adjustments — not just homes that sold for less.
This is what Overassessed does. We find comparable sales from county records, calculate professional-grade adjustments for differences in size, features, and condition, and package the evidence you need — ready to submit.
Your assessed value might be higher than market value for several reasons explained under Proposition 8 — including assessment creep, market corrections, and neighborhood changes.
The Overassessed Filing Guide includes comparable sales data, dollar adjustments, and a ready-to-submit value argument — everything listed above.
See what's included →Key things to know
Filing fee: $290 per parcel, nonrefundable
Santa Clara County charges a $290 nonrefundable filing fee for each formal assessment appeal — one of the highest in California. This fee applies regardless of whether your appeal succeeds. At the county's ~0.79% effective tax rate, your assessed value would need to drop by roughly $36,700 just to break even on the fee in the first year. Start with the free informal review first.
The Board can increase your assessed value
Unlike the informal Prop 8 review (where the Assessor can only reduce or confirm), the formal Santa Clara County Assessment Appeals Board hearing carries a risk: the Board has the authority to increase your assessed value based on evidence presented. Come prepared with solid comparable sales data.
File both: informal by August 1, formal by September 15
File both the free informal review (by August 1) and the formal appeal (by September 15). If the informal review reduces your assessment, you can withdraw the formal appeal. But if you skip the formal filing and the informal review doesn't go your way, you'll have no recourse until next year.
No filing confirmation is sent
After filing your formal appeal, you won't receive any confirmation from the county. The next communication will be your hearing notice, mailed approximately 45 days before your scheduled hearing — which may be 6 to 24 months after filing. Keep a copy of your signed application and proof of mailing.
Value Hearing Officers — a less formal option
For residential properties, you can request a Value Hearing Officer (VHO) by checking “Yes” on Item #9 of the BOE-305-AH form. VHOs are real estate professionals who hear cases in a less formal setting than the full Santa Clara County Assessment Appeals Board. VHO hearings may be scheduled sooner and require only 4 copies of evidence (vs. 6 for the full Board). We recommend this option for all residential appeals.
Source: Santa Clara County Assessment Appeals Board — Value Hearing Officers
Frequently asked questions about property tax appeals
What is the deadline to appeal property taxes in Santa Clara County?
The free informal Prop 8 review must be submitted to the Assessor's Office by August 1. The formal appeal to the Santa Clara County Assessment Appeals Board must be filed between July 2 – September 15. For supplemental assessments (triggered by a change in ownership or new construction), you have 60 days from the date on the notice. If September 15 falls on a weekend, the deadline extends to the next business day.
How much does it cost to appeal my property tax in Santa Clara County?
The informal Prop 8 review is completely free. Filing a formal appeal with the Santa Clara County Assessment Appeals Board costs $290 per residential parcel (effective June 1, 2026), and this fee is nonrefundable regardless of the outcome. If you request Written Findings of Fact from the Board, there is an additional $400 deposit plus $200 per hour for attorney preparation time.
Do I need a lawyer to appeal my property taxes in Santa Clara County?
No. Many Santa Clara County homeowners successfully appeal their assessments without an attorney. For residential properties, you can request a Value Hearing Officer — a less formal setting designed for property owners. You'll need to present comparable sales evidence showing your home's market value is below its assessed value. While you bear the burden of proof, for owner-occupied single-family homes where you've provided all required information, the burden may shift to the Assessor.
What evidence do I need for a property tax appeal in Santa Clara County?
The most important evidence is comparable sales — recent sales of similar homes near your property that closed escrow on or before March 31 of the tax year in question. The Assessor's website offers a Comparable Sales Look-Up tool where you can view the market data used in your assessment. Other helpful evidence includes property photographs, inspection reports, and independent appraisals. Bring 6 copies of all evidence for an Santa Clara County Assessment Appeals Board hearing or 4 copies for a Value Hearing Officer hearing. Do not attach evidence to your application — it's presented at the hearing.
How long does a property tax appeal take in Santa Clara County?
The informal Prop 8 review is the fastest path — results are typically sent by mid-August. A formal appeal can take significantly longer: hearings may be scheduled 6 to 24 months after filing, and with over 5,000 appeals pending, wait times can stretch to the statutory maximum of 2 years. You won't receive any filing confirmation; the first communication is your hearing notice, mailed approximately 45 days before your scheduled date.
What is a Value Hearing Officer in Santa Clara County?
A Value Hearing Officer (VHO) is a real estate professional appointed by the county to hear residential property value disputes in a less formal setting than the full Santa Clara County Assessment Appeals Board. To request a VHO, check "Yes" on Item #9 of your BOE-305-AH application. VHO hearings require 4 copies of your evidence (compared to 6 for the full board) and may be scheduled sooner. For most residential homeowners, the VHO is the recommended hearing option.
Ready to see if you qualify?
Enter your address and we'll compare your assessed value to comparable sales. It takes about 60 seconds.
Overassessed provides estimates based on publicly available data and AI-generated analysis. This is not a formal appraisal, legal advice, or tax advice. Results are not guaranteed, and appeal outcomes depend on county review. Users file their own appeals. AI-generated estimates may differ from actual market values.