San Mateo County, CA Fire Regulations: Fireworks (2026)

Unincorporated San Mateo County prohibits all fireworks under Chapter 5.28 (Fireworks) of the County Ordinance Code, which defines fireworks in section 5.28.020. Even fireworks classified 'Safe and Sane' by the California State Fire Marshal under State Fireworks Law (Health & Safety Code section 12500 et seq.) are illegal to possess, sell, or use in the unincorporated county, all County Parks, state parks, and the Crystal Springs watershed. The Board of Supervisors strengthened the ordinance in May 2021 (File #21-374) for the first time in 35 years, setting a $1,000 fine for all use, sale, and possession violations. The ordinance adds strict-liability provisions: parents and anyone with care, custody, or control of a minor who violates the ordinance are liable, and renters and property owners face fines if fireworks are used on their property (a social-host provision under which a host can be cited even if not personally lighting the fireworks). Repeat violators with two violations within 12 months can be held liable for the county's public-safety response costs, including personnel time, medical treatment, and equipment damage. The ban applies to named unincorporated communities including North Fair Oaks, Emerald Lake Hills, La Honda, San Gregorio, El Granada, Pescadero, Moss Beach, Miramar, Montara, and West Menlo Park.