Online Services


Online Services

The Assessor Division offers a variety of online services to make information access and submission quicker and more efficient.

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Assessor Maps

The Property Maps portal allows you to download Assessor’s maps or Recorded maps such as subdivision maps and parcel maps online for free.

These same maps are also available at the County Recorder Division and may be printed there for a fee. You may purchase an official copy at the office during regular business hours (Monday through Friday, 8 a.m. to 5 p.m.) at:

555 County Center, 1st Floor
Redwood City, CA 94063
650.363.4000 (ext 4771)

Click to search Property Maps

eFile Form 571-L

San Mateo County Assessor uses California Assessors’ Association’s (CAA) Standard Data Record (SDR) system to allow electronic filing of Form 571-L in order to simplify the process of filing annual property statements for businesses.

Link to eFile on SDR

Search Grantor-Grantee Information

The San Mateo County Assessor-County Clerk-Recorder’s Office presents the information on this website as a service to the public. We have tried to ensure that the information in this electronic document is accurate. The Assessor-County Clerk-Recorder’s Office makes no warranty or guarantee concerning the accuracy or reliability of the content at this site or at other sites to which we link. Assessing accuracy and reliability of information is the responsibility of the user. The office shall not be liable for errors contained herein or for any damages in connection with the use of the information contained herein.

You can search recorded documents either online or by coming into our office and using one of our many public terminals. 

Images are not a part of this database for privacy reasons.  If you would like to order a copy of a previously recorded document please see Copy of Recorded Document.

Click Here to Search Index

Online information is for reference only.


Calamity Relief Filing

If a calamity such as fire, earthquake or flood damages or destroys your property, you may be eligible for property tax relief, provided the loss exceeds $10,000. In such cases, the San Mateo County Assessor-County Clerk-Recorder’s Office, Assessor Division will reappraise the property to reflect its damaged condition. If the property is rebuilt in a like or similar manner to the original, the property will retain its previous value for tax purposes.


To qualify for property tax relief, you must file a calamity claim form with the San Mateo County Assessor-County Clerk-Recorder’s Office, Assessor Division within one year from the date the property was damaged or destroyed.


Building Plans Submission Portal
This portal is for authorized permitting agencies only.

Per Revenue and Taxation Code Section 72(c), authorized entities that issue building permits, e.g. City of San Carlos Building Division, shall transmit a copy of the building plans to the county assessor as soon as possible after the final plans are approved.

The Building Plans Submission Portal allows authorized entities to submit PDF copies of building plans to the Assessor Division online.

To upload copies of the approved building plans to the portal, you are required to have an account. If you do not have an account, please fill out the form below. Once your account has been authorized, you will receive an e-mail to change your password.

Please contact us if you have any questions.

Existing Account Holders:

Click here to access the Building Plans Submission Portal

Account Request Form:

Each user within an agency must have their own login. 

This portal is meant for use by building departments or authorized permitting agencies. Please refer to your local Planning & Building Department if you need more information.