Since its establishment, there have been countless small changes to the state highway numbering system as routes are eliminated, combined, or renumbered.

North Carolina alternate routes have been utilized in a multitude of ways, including business, bypass, cut-thru and spurs.

After 1960, nearly all have been decommissioned or converted to business loops, and establishing new alternate routes have been prohibited.

All business routes in the state are set up as a loop, meaning it will separate then converge back to the main highway.

North Carolina, on rare occasion, will utilize other uniquely special routes in the state.