San Mateo County, CA Fire Regulations: Fire Pit Rules (2026)

Fire protection for unincorporated San Mateo County is provided by CAL FIRE / San Mateo County Fire, which enforces the California Fire Code (CCR Title 24, Part 9). Under California Fire Code section 307.4, recreational fires (small wood or charcoal fires for cooking, warmth, or similar) must be kept at least 25 feet from any structure or combustible material and constantly attended until fully extinguished. Portable outdoor fireplaces (chimineas, store-bought fire pits) must be used per the manufacturer's instructions and kept at least 15 feet from any structure or combustible material. Under section 307, open burning is prohibited when atmospheric conditions or local circumstances make fires hazardous, and the fire code official can prohibit fires entirely during high fire danger. Layered on top of the fire code, the Bay Area Air Quality Management District's wood-burning rule (Regulation 6, Rule 3, adopted 2008 and amended through 2025) makes it illegal to burn wood, manufactured logs, pellets, or any solid fuel outdoors, including in fire pits, campfires, and bonfires, on any day a Spare the Air Alert is issued for fine particulate pollution (PM2.5). The rule applies year-round (it originally applied only November-February) and the 2025 amendment lowered the trigger threshold to 25 micrograms per cubic meter. Natural-gas and propane fire features are not affected by the wood-burning ban because they do not emit wood smoke. In Very High Fire Hazard Severity Zones in the Santa Cruz Mountains and coastal hills, CAL FIRE may suspend all outdoor burning during fire season.