South Carolina's freight economy is anchored by three distinct pillars: the Port of Charleston — the largest and deepest port on the U.S. East Coast by container volume — automotive manufacturing centered on the BMW plant in Spartanburg and a growing cluster of suppliers along I-85, and agricultural through-traffic on I-95 and I-26. Charleston is a premier container port handling significant Asia-Pacific trade lanes, generating heavy drayage activity on I-26 (connecting Charleston to Columbia and Spartanburg), I-526 (the Charleston beltway), and local terminal access roads. Spartanburg's BMW plant and the surrounding automotive supplier network drive substantial Class 8 volumes on I-85, I-26, and I-85 Business routes. The South Carolina Department of Motor Vehicles (SC DMV) administers vehicle registration, IRP, and IFTA. The SC Department of Transportation (SCDOT) manages the highway network and issues oversize/overweight permits. South Carolina does not impose a separate weight distance tax, keeping interstate fee structures straightforward. The I-95 corridor through coastal South Carolina carries high through-traffic volumes, particularly during tourist season when RV and personal vehicle traffic adds congestion.
| GVWR | 80,000 lbs federal interstate standard |
| Single axle | 20,000 lbs |
| Tandem axle | 34,000 lbs |
Bridge Formula applies statewide. Overweight permits available from SCDOT for loads exceeding standard limits. Port terminal approach roads may have locally posted limits; carriers should verify before dispatch.
State trucking association: South Carolina Trucking Association
Drayage carriers at the Port of Charleston must hold a TWIC (Transportation Worker Identification Credential) card for terminal access, register with the specific terminal operators they plan to use, and comply with terminal appointment systems. The Port of Charleston operates multiple container terminals (Wando Welch, North Charleston, Hugh K. Leatherman) each with their own credentialing processes.
Automotive freight is a major component of South Carolina's economy. The BMW plant in Spartanburg is one of the largest BMW production facilities in the world and exports a significant share of its output through the Port of Charleston. A substantial supplier network has grown up around it. Carriers serving automotive customers in the I-85 corridor should be prepared for just-in-time delivery windows and potential plant-specific gate access requirements.
The primary corridors are I-95 (the coastal north-south spine), I-26 (the critical link between Charleston and the inland Upstate), I-85 (the Greenville-Spartanburg automotive and manufacturing corridor), and I-77 (Columbia to Charlotte, NC). I-26 and I-526 carry the heaviest port drayage volumes; I-85 carries the highest automotive and general manufacturing freight volumes.
No. South Carolina does not impose a weight distance tax or truck-only mileage fee. Interstate carriers operating in South Carolina pay standard IFTA fuel taxes and registration fees under IRP. This makes South Carolina relatively straightforward compared to states like Oregon (Weight-Mile Tax) or New York (Highway Use Tax).
Verified 2026-05-26.