San Mateo County, CA Soliciting & Door-to-Door: No-Knock Registry (2026)

In unincorporated San Mateo County, posted 'No Soliciting' signs are the primary means of opting out of door-to-door canvassing. A sign posted at the main entrance, gate, or driveway entrance that is clearly visible from the approach is legally sufficient under California Penal Code §602.1 (refusal to leave) and the County's solicitor ordinance. Licensed solicitors are required by their Sheriff-issued permit conditions to review and respect such signs; ignoring a sign is grounds for citation and permit revocation. Individual cities within the County (Redwood City, San Carlos) maintain digital Do Not Knock registries where residents can register their address; licensed solicitors must check the registry before canvassing in those jurisdictions. The County does not currently maintain a unified countywide registry for unincorporated areas. The federal Do Not Call registry covers phone solicitation but not door-to-door. Religious, political, and true charitable canvassing remain exempt from no-soliciting sign requirements under First Amendment protections, though many courts enforce against repeated/aggressive exempt canvassers under trespass statutes.