South Carolina OS/OD Overview
Permit Required
Yes – any load exceeding legal size or weight must have a permit from the South Carolina Department of Transportation (SCDOT). Oversize/overweight (OSOW) single-trip and term permits are issued through SCDOT's permitting office.
Legal Limits (Without Permit)
- Width: 8'6"
- Height: 13'6"
- Length: 75' (combo); 53' trailer allowed
- Weight: 80,000 lbs GVW (standard axle limits apply)
Anything over a legal dimension or weight requires an oversize/overweight permit before the move. Superloads beyond routine permit limits require engineering review, route survey, and possible bridge analysis.
Travel Hours
- Standard: Loads over 12' wide travel from one-half hour after sunrise to one-half hour before sunset.
- Restricted widths: Loads over 15' wide are held to highly restricted hours, with curfews in metro areas.
- Holidays: No travel on New Year's Day, Memorial Day, Independence Day, Labor Day, Thanksgiving Day, or Christmas Day.
Escort Requirements (General Guidelines)
| Dimension | Escort Requirement |
|---|---|
| Width > 12' (up to 14') | 1 front escort on 2-lane roads only |
| Width > 14' (up to 16') | 1 front + 1 rear civilian escort |
| Width > 16' | 1 front + 1 rear civilian escort, plus 1 front + 1 rear police escort |
| Height ≥ 16' | 1 front escort with height-measuring device (height pole) |
| Length 125'–150' | 1 rear escort |
| Length > 150' | 1 front + 1 rear escort |
| Rear overhang > 15' (up to 25') | 1 rear escort; red flag required |
Detailed Information
POLICE ESCORTS: For width over 16', one front and one rear police escort are required, in addition to the civilian front and rear escorts.
CIVILIAN ESCORTS: For width over 14' up to 16', one front and one rear civilian escort are required. For width over 12' up to 14', one front escort is required on 2-lane roads only. For length over 150', one front and one rear escort are required; for length 125'–150', one rear escort is required.
HEIGHT POLE: When the load height is 16' or greater, one front escort equipped with a height-measuring device (vertical height indicator) is required.
OVERHANG: For rear overhang over 15' up to 25', one rear escort is required and a red flag must be displayed.
RESTRICTED TRAVEL: Loads over 12' wide may move only from one-half hour after sunrise to one-half hour before sunset. Loads over 15' wide face highly restricted hours with metro-area curfews. No movement is allowed on New Year's Day, Memorial Day, Independence Day, Labor Day, Thanksgiving Day, or Christmas Day.
Additional Notes
- "Oversize Load" signs, red/orange flags, and amber warning lights are required on the load and escort vehicles per SCDOT permit conditions.
- A red flag must be displayed on loads with rear overhang over 15'.
- Permit conditions issued by SCDOT govern the specific move and may impose requirements beyond these general thresholds.
Source: South Carolina DOT — Oversize/Overweight Permits. Informational only — always verify against the live permit office before any move; permit conditions control.
