Seattle, WA Home Business: Signage Rules (2026)

SMC 23.42.050.D.3 opens the door for a home occupation to post identifying signage, but it hands the actual size and illumination rules to Chapter 23.55, the citywide Sign Code. In Neighborhood Residential zones, SMC 23.55.020.D.8 allows exactly one home occupation sign, capped at 5 square feet, and it must be nonilluminated: no backlit, neon, or electric elements are permitted there. The same 5-square-foot cap follows the use into denser zones, but the illumination rule loosens: SMC 23.55.022.D.5 lets a home occupation in a multifamily zone use an electric or externally illuminated sign at the same 5-square-foot limit, and SMC 23.55.028.D.1.f extends that same electric-or-nonilluminated, 5-square-foot allowance to home occupations in NC1 and NC2 neighborhood commercial zones.

Every home occupation sign, regardless of zone, is also bound by the general sign standards that open SMC 23.55.020: the sign must be stationary and cannot rotate, it cannot flash or use a changing-image or message-board display, and it cannot be mounted as a roof sign. Because the sign is treated as accessory to the home occupation itself rather than as a standalone commercial sign, SDCI still reviews it against these limits when it processes complaints or a related business license application. A sign that exceeds 5 square feet, is illuminated where the zone forbids it, or flashes or rotates is out of compliance with Chapter 23.55 even if the home occupation itself is properly conducted under SMC 23.42.050.