Darlington County, SC Sign Regulations: Digital Billboards (2026)

Appendix A, Section 15.7 of the Development Standards Ordinance, added in 2018, permits digital signs and electronically changing message signs as off-site advertising, expressly including the conversion of a preexisting nonconforming off-premises billboard so long as the sign's dimensions stay the same as its current permit. Every message, image or display must remain unchanged for a minimum of six seconds, and the transition from one complete message to the next can take no more than one second. The ordinance bars any appearance of visual dissolve or fading where two messages overlap, and bars flashing, sudden bursts of light, or any video motion, animation or flow within the sign; light intensity and contrast must stay constant across the face.

Each digital sign must carry automatic day/night dimming software that reduces illumination from one hour after sunset to one hour before sunrise, plus a light-sensing device that adjusts brightness as ambient light changes, and scrolling text is prohibited outright. These technical standards sit on top of the siting rules in Section 15.3, the 378/672-square-foot face caps in Section 15.4, and the 40/100-foot height limits in Section 15.5, so a digital sign must clear all of those thresholds as well as its own display rules. A digital sign remains subject to the countywide sign permit process in Section 15.11, requiring planning department review before a building permit and, along an interstate, a South Carolina Department of Transportation permit.

Because Section 15.7 treats a digital conversion as neither a removal nor an expansion of a nonconforming sign, an owner does not lose grandfathered status by upgrading to a digital face, provided the display panel keeps its existing footprint.