Verification of a notary can only be done by the county clerk’s office in the county in which the notary is commissioned. This is indicated on the notary stamp. Only documents containing a JURAT or ACKNOWLEDGMENT can be authenticated. Notary signature verification is for notary public signature only and does not validate the information within the document.

Authentication Certificate (Apostille) Information – click here

Notary Signature authentication service is available in person or by mail in the clerk’s office. 

Bring or mail the notarized document to:

San Mateo County Assessor-County Clerk-Recorder’s Office
Attn: Special Services
555 County Center 1st Floor
Redwood City CA 94063

The seal must clearly show the name of the notary, commission number and date of expiration. All seals and signatures must be original and legible.

When mailing, please provide a self-addressed stamped envelope with check payable to San Mateo County Clerk.

First signature cost is $12 and each additional signature by same notary is $5/each.