San Mateo County, CA Parking Rules: Commercial & Oversized Vehicles (2026)

Section 7.28.070 gives the Board of Supervisors authority to designate, by resolution, parking zones or parking spaces on public highways under County jurisdiction where parking is prohibited for "oversized vehicles," defined for this section as any vehicle over six feet in height, and for any trailer as defined by California Vehicle Code Section 630, whether or not it remains attached to a towing vehicle. The Director of Public Works marks those zones with signs, curb paint, or other practical means. Once marked, no one may stop, park, or leave an oversized vehicle or trailer standing there, attended or not, except to avoid a traffic conflict, respond to an emergency, or follow a peace officer's direction; the section also exempts active loading and unloading, utility-service vehicles, emergency repairs or a tow wait of up to eight hours, emergency-vehicle response, and wheelchair-accessible vans.

A separate, narrower rule targets commercial trucks specifically in residential neighborhoods. Section 7.28.030 makes it unlawful to stop, leave standing, or park any commercial vehicle, attended or not, on a publicly maintained street in a residential zone in the unincorporated county for more than one hour, unless the vehicle is actually being used for lawful business in that zone or is temporarily disabled. That one-hour cap applies in residential districts without a Board resolution or posted signage; the six-foot-height oversized-vehicle zones under Section 7.28.070 require the Board to designate and post them first. Both sections sit in Chapter 7.28, Miscellaneous Parking Regulations, and both are enforced only in the unincorporated area; incorporated Peninsula cities post and enforce their own commercial-vehicle parking limits.