Santa Clara County's 2026 regular assessment appeal window is open from July 2 through September 15. A major 2026 change is the nonrefundable processing fee effective June 1: $290 per parcel or application for residential, vacant-land, and agricultural property, and $675 for commercial, business, and multifamily property with five or more units. Full payment is required before an application is processed. The county also offers a free informal Assessor review, which should be requested before a formal filing because the Clerk's fee is not refundable. FairPath can assemble an owner-managed evidence file and deadline checklist. It does not file, pay the fee, decide whether an informal review or formal appeal is appropriate, state a value for the owner, or represent anyone at a hearing.
Assessment context: A Santa Clara analysis should separate the factored Proposition 13 base-year ceiling from a temporary Proposition 8 decline in market value. A decline-in-value reduction applies only to the appealed tax year and can be restored in a later year up to the factored base-year value. Verify the parcel, notification of assessed value, January 1, 2026 lien date, enrolled land and improvement components, purchase or construction history, and Assessor characteristics. The county spans condominium towers and older houses in San Jose, high-value neighborhoods in Palo Alto and Los Altos, tract housing in Santa Clara and Sunnyvale, hillside and view properties, rural and agricultural land near Morgan Hill and Gilroy, and varied multifamily uses. School area, micro-location, lot utility, renovation quality, effective age, view, traffic, and hillside constraints can outweigh straight-line distance.
Filing process: Use the county's online system or the current Assessment Appeal Application and choose only the assessment and tax year actually disputed. Online filing provides a confirmation and case number. Paper applications may be mailed or delivered but the county says it does not accept application copies by email or fax. Include the correct fee in full; current payment options are cash, check, money order, or credit card, with a service charge for credit cards. Save the application, payment confirmation, attachments, and case number. When the hearing notice arrives, return the signed Appeal Response Form at least 21 days before the hearing. Failing to return it limits the scheduled event to a non-value hearing, and failing to appear may cause denial. All hearings are held in the Appeals Hearing Room at 130 W. Tasman Drive in San Jose under the county's current procedure.
Evidence to review: For a January 1, 2026 value dispute, focus on arm's-length sales close to that date and never later than 90 days after it. Santa Clara's hearing guidance says comparability turns on timing and similarities in building size, lot size, location, view, use, and amenities. Create an exhibit table with APN, sale date, verified price, municipality and neighborhood, property type, living area, lot, age, remodel status, quality, condition, parking, view, and adjustments. Add dated photographs, inspections, permits, bids, or engineering material for defects or incomplete work. The hearing package must be operationally ready: the county requires six extra document copies for a three-member Appeals Board and four extra copies for a Value Hearing Officer. A Rule 305.1 information exchange can be initiated before 30 days prior to hearing, with valuation information supplied when the request is made.
Current deadline guidance: 2026 regular assessment appeals: July 2 through September 15, 2026. Santa Clara County's regular filing period for applications appealing the 2026 regular assessment is July 2 through September 15, 2026. The regular period includes decline-in-value and certain base-year, personal-property, and penalty assessment appeals. Supplemental and escape assessments use separate notice-specific timelines.
Beginning June 1, 2026, Santa Clara imposed a $290 filing fee for residential, vacant-land, and agricultural parcels and a $675 fee for larger multifamily, commercial, and business matters.
The Assessor offers a free informal assessment review, but the county advises requesting it before filing because the formal appeal processing fee is nonrefundable.
Eligible single-family homes, condominiums, cooperatives, and properties with four or fewer dwelling units may choose a less formal Value Hearing Officer instead of a three-member Board.
Santa Clara requires a signed hearing response 21 days before the hearing and asks for six extra evidence copies before a Board or four before a Value Hearing Officer.
Official filing authority: County of Santa Clara Assessment Appeals Division. https://sccgovaa.custhelp.com/
Source: County of Santa Clara Office of the Clerk of the Board, Assessment Appeal Dates and Deadlines, https://cob.santaclaracounty.gov/appeal-your-property-taxes/assessment-appeal-dates-and-deadlines. Reviewed 2026-07-16.
Source: County of Santa Clara Office of the Clerk of the Board, Appeal Your Property Taxes, https://cob.santaclaracounty.gov/appeal-your-property-taxes. Reviewed 2026-07-16.
Source: County of Santa Clara Office of the Clerk of the Board, Assessment Appeals Hearing Preparation, https://cob.santaclaracounty.gov/appeal-your-property-taxes/assessment-appeals-hearing-preparation. Reviewed 2026-07-16.
Source: County of Santa Clara Office of the Clerk of the Board, Value Hearing Officers, https://cob.santaclaracounty.gov/appeal-your-property-taxes/resources/assessment-appeals-board/value-hearing-officers. Reviewed 2026-07-16.