On June 19, 2007, the South Carolina Department of Transportation Commission approved the change to the signs marking the primary state highways from the black-and-white to the blue-and-white design, which features an outline of the state, the palmetto tree and crescent symbol from the state flag, and the words "SOUTH CAROLINA" spelled out along on the top of the highway shield.

[2] South Carolina uses a wide shield for all routes, regardless of number of digits.

[3] South Carolina utilizes a numbering system to keep track of all non-interstate and primary highways that are maintained by SCDOT.

First appearing in 1947[citation needed] (when a huge amount of highways were cancelled or truncated), the "state highway secondary system"[4] carries the number of the county followed by a unique number for the particular road.

South Carolina Ferry System is a branch of SCDOT that is responsible for the operation of over two dozen ferry services that transport passengers and vehicles to several islands along the James Island outside of Charleston in South Carolina.