Caldwell, ID Sign Regulations: Digital Billboards (2026)

Caldwell treats electronic message centers (EMCs) and changeable copy signs as an add-on to a monument sign rather than a stand-alone digital billboard. Under § 10-02-06-8(2)(B), only one EMC or changeable copy sign is allowed per property in the C-1, C-2, C-3, C-4, H-C, M-1, M-2 and I-P districts, and it must be part of a permitted freestanding monument sign, with the digital portion capped at twenty-five percent of that monument sign's permitted square footage. Installing one requires both a special use permit and a sign permit before any work begins.

Every EMC must carry automatic dimming controls, either a hardwired photocell or software settings, so the display's night-time brightness drops to an acceptable level as ambient light falls. Display behavior is regulated by zone: in the C-1 district, each message or frame must display for at least eight seconds, with transitions between messages capped at three seconds and limited to fades, dissolves, and similar effects. In every other commercial and industrial zone, EMCs get more latitude on display features, but flashing is banned outright, and full-motion video or streamed film content is prohibited unless a business obtains a separate special use permit for it.

Caldwell's residential sign schedule, § 10-02-06-7(2)(B), imposes the same twenty-five-percent-of-monument-sign cap and dimming requirement on non-residential uses located inside residential zoning districts, with an eight-second minimum display time citywide in that schedule.