Assessor
Assessor
The Assessor is responsible for determining the assessed value of all taxable property located in San Mateo County. With approximately 237,000 assessments each year, the Assessor Division creates the official record of taxable property (local assessment roll), shares it with the County Controller and Tax Collector, and makes it publicly available. The local assessment roll is determined by identifying, mapping, inspecting, and calculating the assessed value for all real (land and structures) and business properties. Typically, property tax is 1% of the assessed value, plus an amount to amortize voter-approved bonds and any fees for special assessments or charges such as mosquito abatement or sewer fees.
The division assesses over 221,000 units on the secured roll and 16,000 units on the unsecured roll. In addition, the Office processes approximately 50,000 transfer documents, 24,000 building permits, 143,000 exemptions and 10,000 business property statements annually.
San Mateo County claims within its boundaries a wealth of land, buildings, and taxable properties with an assessed value of more than $206 billion. The property tax revenues generated from these assets are vital to maintaining local government operations and public services.
San Mateo County - Combined Property Assessment Roll - Historical Values
For more information, please read 2018-2019 Assessor's Annual Report.
Real Property
Real Property Assessment
The Assessor Division compiles a roll of property tax assessments for delivery to the County Controller by July 1 each year. This “Local Assessment Roll” covers more than 237,000 assessments countywide, value in excess of $206 billion.
A copy of the Local Assessment Roll is available at the Assessor Division front counter for public inspection. The Assessor Division also reassesses personal property each year.
Business Personal Property
The Assessor sets the value of the tangible assets possessed by more than 15,000 businesses operating in San Mateo County, thereby establishing their taxable value. The Assessor also sets the value of 4,000 boats and 400 private aircraft owned here.
Private citizens get answers to questions about their property from the Assessor. These include how to file business personal property statements and, through the County Clerk, how to file fictitious business name statements.
Online Services
The Assessor Division offers a variety of online services to make information access and submission quicker and more efficient.
Tax Saving Programs
Exemptions, Exclusions and Tax Relief Programs that provide property tax relief to California homeowners
Assessment Roll Summaries
Secured, Unsecured and Combined Roll Summaries
The assessment roll is a listing of assessed property within the county. It includes some identifying features such as a parcel or account number, the assessed owner, and a breakdown of the assessed values and exemptions.The summary is a breakdown by cities and unincorporated areas of the county.
- Secured Roll - Fiscal Year 2017-2018
- Unsecured Roll - Fiscal Year 2017-2018
- Combined Roll - Fiscal Year 2017-2018
- Unsecured Roll - Fiscal Year 2016-2017
- Combined Roll - Fiscal Year 2016-2017
- Secured Roll - Fiscal Year 2015-2016
- Unsecured Roll - Fiscal Year 2015-2016
- Combined Roll - Fiscal Year 2015-2016
- Secured Roll - Fiscal Year 2014-2015
- Unsecured Roll - Fiscal Year 2014-2015
- Combined Roll - Fiscal Year 2014-2015
- Secured Roll - Fiscal Year 2013-2014
- Unsecured Roll - Fiscal Year 2013-2014
- Combined Roll - Fiscal Year 2013-2014
- Secured Roll - Fiscal Year 2012-2013
- Unsecured Roll - Fiscal Year 2012-2013
- Combined Roll - Fiscal Year 2012-2013
- Secured Roll - Fiscal Year 2011-2012
- Unsecured Roll - Fiscal Year 2011-2012
- Combined Roll - Fiscal Year 2011-2012
- Secured Roll - Fiscal Year 2010-2011
- Unsecured Roll - Fiscal Year 2010-2011
- Combined Roll - Fiscal Year 2010-2011
- Secured Roll - Fiscal Year 2009-2010
- Unsecured Roll - Fiscal Year 2009-2010
- Combined Roll - Fiscal Year 2009-2010
- Secured Roll - Fiscal Year 2008-2009
- Unsecured Roll - Fiscal Year 2008-2009
- Combined Roll - Fiscal Year 2008-2009
- Secured Roll - Fiscal Year 2007-2008
- Unsecured Roll - Fiscal Year 2007-2008
- Combined Roll - Fiscal Year 2007-2008
- Secured Roll - Fiscal Year 2006-2007
- Unsecured Roll - Fiscal Year 2006-2007
- Combined Roll - Fiscal Year 2006-2007
- Secured Roll - Fiscal Year 2005-2006
- Unsecured Roll - Fiscal Year 2005-2006
- Combined Roll - Fiscal Year 2005-2006
- Secured Roll - Fiscal Year 2004-2005
- Unsecured Roll - Fiscal Year 2004-2005
- Combined Roll - Fiscal Year 2004-2005
- Secured Roll - Fiscal Year 2003-2004
- Unsecured Roll - Fiscal Year 2003-2004
- Combined Roll - Fiscal Year 2003-2004
- Secured Roll - Fiscal Year 2002-2003
- Unsecured Roll - Fiscal Year 2002-2003
- Combined Roll - Fiscal Year 2002-2003
- Secured Roll - Fiscal Year 2001-2002
- Unsecured Roll - Fiscal Year 2001-2002
- Combined Roll - Fiscal Year 2001-2002
- Secured Roll - Fiscal Year 2000-2001
- Unsecured Roll - Fiscal Year 2000-2001
- Combined Roll - Fiscal Year 2000-2001
- Secured Roll - Fiscal Year 1999-2000
- Unsecured Roll - Fiscal Year 1999-2000
- Combined Roll - Fiscal Year 1999-2000
- Secured Roll - Fiscal Year 1998-1999
- Unsecured Roll - Fiscal Year 1998-1999
- Combined Roll - Fiscal Year 1998-1999
- Secured Roll - Fiscal Year 1997-1998
- Unsecured Roll - Fiscal Year 1997-1998
- Combined Roll - Fiscal Year 1997-1998
- Secured Roll - Fiscal Year 2016-2017
- Combined Roll - Fiscal Year 2018-2019
- Secured Roll - Fiscal Year 2018-2019
- Unsecured Roll - Fiscal Year 2018-2019
- Unsecured Roll - Fiscal Year 2019-2020
- Secured Roll - Fiscal Year 2019-2020
- Combined Roll - Fiscal Year 2019-2020
- Local Combined Roll - Fiscal Year 2020-2021
- Local Secured Roll - Fiscal Year 2020-2021
- Local Unsecured Roll - Fiscal Year 2020-2021
- Read more
Glossary of Terms
In this section, you will find an explanation of the terms used in various mailings sent from the Assessor Division.
Appraised Value
A property’s value as determined by the sale amounts of comparable properties. The current appraised value is usually the property’s current market value.
Assessor’s Parcel Number
The Assessor’s identification number for a specific property. Also referred to as the account number, folio number and UPC in different regions.