Tustin, CA Home Business: Signage Rules (2026)

Under the City of Tustin's Home Occupation Questionnaire definition (Tustin City Code Sections 9271gg and 9297), a home occupation must involve 'no exterior display' and 'no alteration of the residential appearance of the premises.' Together these standards prohibit a home-based business from posting an exterior sign that would advertise the business or alter how the property reads as a residence. The city's general business forms also note that using a P.O. box or commercial mailbox as the business address is a misdemeanor, reinforcing that the home occupation must stay low-profile and residential in character. Commercial and on-premise sign standards generally are set out in Tustin City Code Article 9, Chapter 4 (Sign Regulations); however, those sign allowances apply to commercial and nonresidential contexts rather than authorizing business advertising signs at a home-occupation residence. Homeowners who want any sign beyond what zoning allows in a residential district would need to confirm with the Tustin Planning Division. In practice, because the home occupation cannot change the residential appearance, a Tustin home business operates without exterior business signage.