Request for Decline in Market Value Reassessment

New this year is an option to file your Prop 8 review by e-form:

1. On your claim form, provide the Assessor with information that supports your opinion that the market value for your property is less than the assessed value. The best supporting documentation is information on sales of comparable properties. Provide at least one comparable sale that sold as close to January 1 as possible, but no later than March 31.

Note: For the e-form option, at least one comparable sale must be provided. Requests supported by information other than comparable sales, such as income data for commercial properties, must be submitted manually.

2. An appraiser will review your claim form and the information you provide. Other sales information available to the Assessor may also be considered. If the market value as of January 1 is less than the trended base value, your assessed value will be lowered to the market value for the fiscal year beginning on July 1. The adjusted value will be reflected on your annual tax bill. If the current market value is higher than the trended base value, no change in assessed value will be made.

Note: You must provide your Parcel Number (also know as Assessor’s Parcel Number) when filling out any of the forms below. If you do not know your Parcel Number, please click HERE

3. If you disagree with the Assessor’s findings, you may file an appeal with the Assessment Appeals Board. You must file your appeal between July 2 and September 15 for your annual tax bill. If September 15 falls on a Saturday, Sunday, or a legal holiday, an application is valid if either filed or postmarked by the next business day.


E-Form Submission


E-Form Submission


Click here to be directed to the fillable PDF form

Attention!A Message to Boat Owners

Dear Alameda County Residents:

Many vessel owners will see an increase in their 2022 property tax valuations!
The valuation factors calculated by the State Board of Equalization and provided to California County Assessors through LTA 2022/003 indicate an increase in 2022 values between 20-24% depending on the type of vessel. The State Board of Equalization reviews average retail sale prices for new and used powerboats, sailboats, and personal watercraft annually to develop the valuation factors. Per their research, these vessels have experienced large appreciation in value compared to 2021.

For more information please click here.


The Alameda County Assessor’s Office