Kennewick, WA Home Business: Signage Rules (2026)

KMC 18.42.090(1)(f) is blunt about advertising: "There must be no exterior advertising, except a residential use sign." That carve-out sign is separately defined in KMC 18.09.1760, and the definition does the real work of limiting it: "Residential Use Sign means a sign displayed on the side of a residential structure or inside of a window, not more than one square foot and unilluminated." In practice, that allows a home business exactly one small sign, either mounted on the side of the house or placed inside a window, capped at one square foot, and it can't be lit in any way, no backlighting, no spotlighting, no internal illumination.

Subsections (g) and (h) of the same home occupation section close off the other common ways a home business tries to signal its presence to the street: "There must be no window displays nor commodities displayed outside the building," and "There shall be no retail sales on the premises." Together, the three subsections mean a home occupation can be identified from the outside only by that single, small, dark sign, not by product displays, outdoor merchandise, or any indication that walk-in retail is happening inside.

These standards are conditions of the underlying home occupation approval process in KMC 18.42.090: in R districts, the Planning Director denies an application under subsection (2) if the applicant "cannot substantially meet each and every one" of the listed criteria, signage included, and even an approved home occupation isn't final under subsection (3) until the operator has also obtained a business license.