# List of Interstate Highways in South Carolina

There are 11 Interstate Highways—5 primary and 6 auxiliary—that exist entirely or partially in the U.S. state of South Carolina. As of December 31, 2013, the state had a total of 850.80 miles (1,369.23 km) of interstate and 11.80 miles (18.99 km) of interstate business, all maintained by the South Carolina Department of Transportation (SCDOT).

## Primary Interstates

| Number | Length (mi) | Length (km) | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes |
| I-20 | 141.51 | 227.74 | I-20 at the GA state line | I-95 / I-20 Bus. in Florence | 01964-01-011964 | current | |
| I-26 | 220.95 | 355.58 | I-26 at the NC state line | US 17 in Charleston | 01960-01-011960 | current | |
| I-73 | — | — | US 17 in Briarcliffe Acres | Future I-73 at the NC state line | proposed | — | Future designation along SC 22 |
| I-74 | — | — | Future I-74 at the NC state line | US 17 in Garden City | proposed | — | Future designation along SC 31 |
| I-77 | 91.05 | 146.53 | I-26 in Cayce | I-77 / US 21 at the NC state line | 01975-01-011975 | current | |
| I-85 | 106.28 | 171.04 | I-85 at the GA state line | I-85 at the NC state line | 01959-01-011959 | current | |
| I-95 | 198.76 | 319.87 | I-95 at the GA state line | I-95 at the NC state line | 01968-01-011968 | current | |
| Proposed and unbuilt ||||||||

## Auxiliary Interstates

| Number | Length (mi) | Length (km) | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes |
| I-126 | 3.680 | 5.922 | I-26 / US 76 in Columbia | US 21 / US 76 / US 176 / US 321 in Columbia | 01961-01-011961 | current | |
| I-185 | 17.7 | 28.5 | I-385 in Mauldin | US 29 in Greenville | 01961-01-011961 | current | Toll road between I-385 and I-85. |
| I-326 | 5.24 | 8.43 | I-26 in Cayce | SC 48 in Columbia | 01976-01-011976 | 01995-01-011995 | Was an unsigned designated route, replaced by I-77. |
| I-385 | 42.16 | 67.85 | I-26 near Clinton | US 276 in Greenville | 01962-01-011962 | current | |
| I-520 | 7.72 | 12.42 | I-520 at the GA state line | I-20 in North Augusta | 02004-01-012004 | current | |
| I-526 | 19.26 | 31.00 | US 17 / SC 7 in Charleston | I-526 Bus. / US 17 in Mount Pleasant | 01989-01-011989 | current | |
| I-585 | 2.25 | 3.62 | US 176 / US 221 / SC 9 in Spartanburg | I-85 Bus. / US 176 near Spartanburg | 01959-01-011959 | current | |
| Former ||||||||

## Business routes

| Number | Length (mi) | Length (km) | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes |
| I-20 BS | 2.110 | 3.396 | I-20 / I-95 in Florence | US 76 Conn. / West Evans Street in Florence | 01970-01-011970 | current | |
| I-85 BL | 8.770 | 14.114 | I-85 northwest of Fairforest | I-85 east of Valley Falls | 01995-01-011995 | current | Freeway-grade business loop |
| I-126 BS | 0.60 | 0.97 | I-126 / US 21 / US 76 / US 176 / US 321 in Columbia | US 21 / US 76 / US 176 / US 321 in Columbia | 01980-01-011980 | — | |
| I-385 BS | 0.490 | 0.789 | I-385 / US 276 in Greenville | US 29 / SC 183 in Greenville | 01962-01-011962 | current | Unsigned business spur |
| I-526 BS | 1.570 | 2.527 | I-526 / US 17 in Mount Pleasant | SC 703 in Mount Pleasant | 01992-01-011992 | current | |
| I-585 BS | 1.60 | 2.57 | US 29 / US 176 / SC 9 in Spartanburg | I-585 / US 176 / US 221 / SC 9 in Spartanburg | 01959-01-011959 | — | |
| Former ||||||||