South Carolina Truck Weight and Size Limits
Legal limits for a truck in South Carolina without a permit: Interstate axle and gross weights, height, width, and semitrailer length, each with its official source.
South Carolina limits at a glance
| Limit | South Carolina | Source |
|---|---|---|
| Interstate gross weight | 80,000 lb | FHWA, Compilation of Existing State Truck Size and Weight Limit Laws (Report to Congress, May 2015), Appendices A and B |
| Interstate single axle | 20,000 lb | FHWA, Compilation of Existing State Truck Size and Weight Limit Laws (Report to Congress, May 2015), Appendices A and B |
| Interstate tandem axle | 35,200 lb | FHWA, Compilation of Existing State Truck Size and Weight Limit Laws (Report to Congress, May 2015), Appendices A and B |
| Width (National Network) | 102 in | 23 CFR 658.15, Width (eCFR) |
| Height | 13 ft 6 in (automobile transporters and saddle mounts 14 ft) | S.C. Code § 56-5-4060 |
| Semitrailer length | 53 ft on the Interstate and designated highways; a 53-ft trailer needs a rear underride guard and 41 ft or less from the kingpin to the center of the rear axle (or tandem) | S.C. Code § 56-5-4070(A)(1) |
| Grandfathered semitrailer length | 48 ft | 23 CFR part 658, Appendix B, Grandfathered Semitrailer Lengths (eCFR) |
Interstate weight limits
Federal law sets the Interstate limits at 20,000 lb on a single axle, 34,000 lb on a tandem, and 80,000 lb gross, with the bridge formula on every axle group (23 CFR 658.17). States may keep higher limits they had before the federal limits took effect ("grandfather rights").
FHWA lists a grandfathered 35,200 lb tandem on all highways, including the Interstate. South Carolina's summary adds that this applies when GVW is 75,185 lb or less (and the bridge formula then doesn't apply).
FHWA on South Carolina: South Carolina has a grandfather provision under Federal law (Grandfathered Weight Provisions 1974) to allow vehicles to operate up to 35,200 lbs. on a tandem axle on all highways, including the Interstate System.
Bridge formula check with South Carolina limits
A 5-axle tractor-trailer is filled in. Change the spacings and weights to match your rig; the limits for single axles, tandems, and gross are South Carolina's Interstate limits.
Your result
South Carolina limits off the Interstate
FHWA's summary of South Carolina law for trucks in regular operation (no permit), including non-Interstate highways. It reflects state law as of October 1, 2012; check the state for later changes.
- Single axle
- 10,000 lbs. per wheel / 20,000 lbs. on Interstate highways including enforcement tolerance
- Tandem axle
- 35,200 lbs. on all highways if GVW is 75,185 lbs. or less* / 36,000 lbs. on non-Interstate highways
- Tridem axle
- Per State weight table
- Gross weight
- 73,280 lbs. on non-Interstate highways / 80,000 lbs. on Interstate highways
- Other
- 10 percent tolerance on non-Interstate highways (S.C. Code Ann. §56-5-4160[A])
Where South Carolina allows more than federal limits
- South Carolina State statute allows for several axle and GVW exemptions for various types of vehicles and commodities.
- South Carolina State statute allows for several tolerances, up to 15 percent, for axle weights and GVW for specific vehicles and commodities.
Height, width, and length
- Width: 102 inches. States may not set a width limit of more or less than 102 inches on the National Network (23 CFR 658.15(a)). Permits can allow wider loads.
- Height: 13 ft 6 in (automobile transporters and saddle mounts 14 ft). There is no federal height limit; each state sets its own.
- Semitrailer length: 53 ft on the Interstate and designated highways; a 53-ft trailer needs a rear underride guard and 41 ft or less from the kingpin to the center of the rear axle (or tandem)
- Grandfathered semitrailer length: 48 ft. The minimum semitrailer length the state must allow in a tractor-semitrailer combination on the National Network, based on lengths legal in the state on December 1, 1982. Federal law also requires at least 48 ft (23 CFR 658.13(b)(1)).
Over these limits you need a permit. South Carolina oversize/overweight permits (877-349-7190).
South Carolina compared with neighboring states
| State | Gross | Single | Tandem | Height | Semitrailer |
|---|---|---|---|---|---|
| South Carolina | 80,000 lb | 20,000 lb | 35,200 lb | 13 ft 6 in | 53 ft on the Interstate and designated… |
| Georgia | 80,000 lb | 20,340 lb | 34,000 lb | 13 ft 6 in | 53 ft |
| North Carolina | 80,000 lb | 20,000 lb | 38,000 lb | 14 ft | 53 ft |
| Tennessee | 80,000 lb | 20,000 lb | 34,000 lb | Pending | Pending |
| Virginia | 80,000 lb | 20,000 lb | 34,000 lb | 13 ft 6 in | 48 ft |
Sources
Source: FHWA, Compilation of Existing State Truck Size and Weight Limit Laws (Report to Congress, May 2015), Appendices A and B · Effective Oct 1, 2012 · Last verified Sep 28, 2026
Source: FHWA, Compilation of Existing State Truck Size and Weight Limit Laws (Report to Congress, May 2015), Appendix A: South Carolina · Effective Oct 1, 2012 · Last verified Sep 28, 2026
Source: 23 CFR 658.15, Width (eCFR) · Last verified Sep 28, 2026
Source: 23 CFR part 658, Appendix B, Grandfathered Semitrailer Lengths (eCFR) · Last verified Sep 28, 2026
Source: S.C. Code § 56-5-4070(A)(1) · Last verified Sep 28, 2026
Source: FHWA, Oversize/Overweight Load Permits: State permit contacts · Last verified Sep 28, 2026
Limits change, and cities, counties, and posted bridges can set lower ones. Check with South Carolina before you run a load near the limits. Page data last verified Sep 28, 2026.