Bonner County, ID Outdoor Lighting: Billboard Lighting (2026)

The Bonner County sign standards never use the word billboard. What the code does is regulate every illuminated sign and advertising structure in section 12-442, and section 12-815 separately defines an outdoor advertising structure as a structure for the permanent display of off premises advertising, meaning a commercial message about a business not conducted on the premises where the sign is located.

Subsection A keeps beams and illumination off any public thoroughfare, highway, sidewalk or navigable water. Subsection B is the core limit: all internally illuminated signs are prohibited, with three exceptions, namely neon signs, dark opaque signs where light only shines through the individual letters, and logos no more than ten (10) square feet in size. Subsection C states a preference for externally illuminated signs that are downwardly directed. Subsection D requires all wiring, fittings and materials used for electrically illuminated signs or advertising structures to follow the electrical codes established by the state of Idaho.

Other sign rules sit beside the lighting rule. Section 12-443 D prohibits moving, rotating or flashing signs, with the exception of time and temperature displays, for nonresidential uses in the commercial, industrial, recreation, alpine village and rural service center districts. Section 12-441 B bars any sign or advertising structure from being attached, installed or erected so as to affect an emergency access, fire escape, door or window, and 12-441 C requires every sign to be plainly marked with the name of the person, firm or corporation responsible for maintaining it. Section 12-441 D limits sign subject matter to things occurring on the premises, with off premises temporary event signs allowed for a maximum of thirty (30) days total during one calendar year. Table 4-4 in 12-443 caps a freestanding sign at 64 square feet and 10 feet in height along a state highway with a posted speed limit of 55 miles per hour or more.

The county's stated purpose for its design standards, in section 12-450 F, is to preserve rural dark skies by reducing nighttime glare and light pollution.