San Mateo County, CA Animal Ordinances: Breed Restrictions (2026)

There is no breed-specific ban in unincorporated San Mateo County. The County Ordinance Code, Title 6, Chapter 6.04, regulates problem dogs by behavior rather than breed: it defines 'dangerous animal' and 'vicious animal' as separate categories (Section 6.04.010) and provides for permits, hearings, and, for vicious animals, destruction. PHS/SPCA confirms these are legally defined, behavior-based designations and that no breed-specific restrictions apply in San Mateo County. Under Section 6.04.100, a person may keep no more than two dangerous animals at any one household without prior written approval, and a dangerous-animal permit can require a secure enclosure, a warning sign at all entrances, microchipping, spay/neuter within 45 days, a dangerous-animal tag, financial responsibility (a bond or insurance of $300,000 per animal), and, when off the property, a leash not exceeding four feet. California state law reinforces the no-breed-ban approach: the Food & Agricultural Code prohibits cities and counties from adopting breed-specific bans on owning or licensing dogs, while allowing breed-specific mandatory spay/neuter or breeding programs. Owners therefore cannot be barred from keeping any breed in the unincorporated County, but an individual dog of any breed can be declared dangerous or vicious after a biting or attacking incident.