San Mateo County, CA Short-Term Rentals: Occupancy Limits (2026)

San Mateo County caps short-term rental occupancy in the unincorporated Coastal Zone through a performance standard built into every permit. Section 6401.3(6)(a) sets the maximum number of short-term tenants at two (2) persons per bedroom rented, plus two (2) additional persons. The ordinance gives a worked example: if one bedroom is rented, up to four short-term tenants are permitted. Children under twelve (12) years of age are not counted toward this maximum, so a family with young children can exceed the headline number on account of those children. Because the formula is tied to bedrooms 'rented,' the limit scales with how much of the home is offered; a three-bedroom whole-home rental would allow up to eight tenants (3 x 2 + 2), and so on. This occupancy figure also drives the parking requirement: under Section 6401.3(6)(b), a single-family STR with a maximum occupancy exceeding eight short-term tenants must provide at least two on-site parking spaces instead of one. The owner must post the allowed number of tenants, along with the other performance standards, in a prominent, readily visible location inside the unit per Section 6401.3(6)(g). The local contact person is expected to ensure tenants do not overcrowd the site.