Skip to main content
CityRuleLookup

San Mateo County, CA Animal Ordinances: Cat Rules (2026)

Some Restrictions
Compiled from the official code textEditor Martyn O'NeillLast verified September 2026

Key Facts

License required
cats over 3 months old
First due
age 3 months or 60 days after acquisition
Altered-cat fee
lower than unaltered-cat fee
Alternative
3-year license with 3-year rabies proof

Summary

Unincorporated San Mateo County requires an annual license for every cat over three months old, with lower fees for altered cats and a lifetime tag.

City-specific rules exist: Redwood City has its own cat rules rules that differ from San Mateo County's county-level regulations. If you live in Redwood City, check the city-specific page instead.

An annual license shall be obtained, and an annual license fee shall be paid by the Owner for every dog or cat over the age of three (3) months owned or kept in unincorporated San Mateo County, and all cities within the County which adopt this Chapter. Said annual license fee shall be first due when the animal reaches three (3) months of age or within sixty (60) calendar days after the dog or cat is acquired, and due on the expiration date of the rabies vaccination and each year thereafter.(2)New residents shall have sixty (60) calendar days in which to acquire such license.(3)Persons renewing their license shall have thirty (30) calendar days following their due date before being found delinquent and assessed a late penalty.(4)The fee for such license shall be as set forth in section 6.04.350 of this Chapter. The fee paid for the licensing of altered dogs and cats shall be less than said license fee for unaltered cats or dogs upon presentation of the proper certification.

View official code

Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 47).

Full Breakdown

Ordinance Code § 6.04.040 requires an annual license and fee for every cat over three months old kept in unincorporated San Mateo County (and cities that adopt the chapter). The fee is due when the cat turns three months old or within 60 days of acquisition, and again on the rabies-vaccination expiration date each year; owners may instead get a three-year license with proof of a three-year rabies vaccination. Altered cats pay a lower fee, and owners over 60 get a discount. A lifetime tag is issued on payment and must stay on the cat's collar.

Violations & Fines

Unpaid license fees after the due date draw a late fee under § 6.04.350 and can result in an administrative citation; renewal delinquency applies after 30 days past the due date.

Frequently Asked Questions

Do I need a license if my cat stays indoors only?
Section 6.04.040 licenses every cat over three months old kept in the unincorporated area: it doesn't exempt indoor-only cats.
Is there an exemption for feral cat colony caretakers?
Yes, but it's set out separately in § 6.12.020(d)'s registered-caretaker exemption for barn or feral cat colonies, not in the general licensing section.

Sources & Official References

Other rules in San Mateo County

All San Mateo County rules

California rules heatmap·Compare San Mateo County to another location·View the California animal ordinances overview

Get notified when Cat Rules in San Mateo County, CA changes

We'll email you the moment we detect a change in the code. No spam, unsubscribe anytime.

We'll never sell or share your email. One-click unsubscribe in every email.

See something wrong?

Help us keep this page accurate. If you notice an error or outdated information, let us know.

Cat Rules in Cities Across San Mateo County