By Evan Reid, Founder of Haul Handbook · Updated Aug 5, 2026
South Carolina permits oversize and overweight moves through the SCDOT OSOW Permit Office in Columbia, using the Safehaul online system. A single trip permit is $30 and an annual multiple trip permit is $100, on a fee schedule SCDOT says was last revised July 1, 2012. The state's legal weight ceiling is the number to watch: 73,280 pounds on a five-axle combination off the interstate, not 80,000, with 80,000 available on the interstate system through the federal bridge formula.
Who issues what in South Carolina
The permit pages
South Carolina-specific requirements
South Carolina splits motor carrier regulation across three agencies and prices trucks in a way no neighbouring state copies. SCDMV Motor Carrier Services issues the Certificate of Compliance for intrastate for-hire freight and runs IRP, IFTA, and the road use fee. The Public Service Commission, with the Office of Regulatory Staff, certificates passenger, household goods, and hazardous waste for disposal carriers. SCDOT permits oversize and overweight moves. The road use fee is the fact that surprises carriers most: large commercial motor vehicles pay a state fee at registration in place of county property tax, and trailers pay a one-time $87 fee for life.
The road use fee replaced property tax on big trucks
One hundred percent of the fair market value of all large commercial motor vehicles and buses registered for use in South Carolina is exempt from property tax and is instead subject to a road use fee, which is in lieu of all ad valorem taxes and of any road use or other vehicle-related fee a political subdivision might impose. A large commercial motor vehicle is one with a gross vehicle weight greater than 26,000 pounds that is registered under the International Registration Plan or used on a highway to transport property. Vehicles at or below 26,000 pounds are small commercial motor vehicles and stay on the ordinary property tax and registration track. The regime took effect January 1, 2019 under 2017 Act No. 40 (H.3516), Section 8.A.
How the road use fee is actually calculated
SCDMV assesses the fee annually on fair market value at an assessment ratio of nine and one half percent, with fair market value found by depreciating the gross capitalized cost of each vehicle by an annual percentage allowance down to ten percent of cost (year one 0.90, year two 0.80, and so on). The millage applied is a statewide average for all purposes for the preceding calendar year; the Department of Revenue, with the Revenue and Fiscal Affairs Office, calculates it by June 1 for the following calendar year, and SCDMV publishes the previous year's average millage by July 1. The fee is due to SCDMV at the same time and in the same manner as the registration fees under S.C. Code Ann. 56-3-660, and a carrier paying registration quarterly must pay the road use fee in the same quarterly installments.
Trailers pay $87 once and never again
One hundred percent of the fair market value of semitrailers and trailers commonly used in combination with a large commercial motor vehicle is exempt from property tax. In place of property tax and the ordinary registration requirements in S.C. Code Ann. 56-3-110 and 56-3-700, a one-time $87 fee is payable to SCDMV on every semitrailer and trailer currently registered and on each one before it is placed in service. The fee is in lieu of any local road use fee, registration fee, or other vehicle-related fee a political subdivision might impose, and SCDMV designs a permanent tag for display on the exterior rear of the trailer. Twelve dollars of the $87 stays with SCDMV to administer the fee and the remaining seventy-five dollars is distributed to local governments.
Legal gross weight off the interstate is 73,280 pounds, not 80,000
South Carolina caps a combination of vehicles with five or more axles at 73,280 pounds on any section of highway other than the interstate. The 80,000-pound figure carriers expect is available only on the interstate system, and only through the federal bridge formula in S.C. Code Ann. 56-5-4140(A)(4). Interstate gross weight may not exceed 75,185 pounds including all enforcement tolerances except under that formula, and the interstate single-axle and tandem caps are 20,000 and 35,200 pounds including tolerances.
A 10 percent enforcement tolerance, 15 percent for forest products and sod
The ten percent enforcement tolerance in S.C. Code Ann. 56-5-4160 applies to the state gross weight limits, but never lifts a vehicle above the interstate caps. The tolerance rises to fifteen percent for a vehicle or trailer transporting unprocessed forest products, and separately for one transporting sod, in both cases only on noninterstate routes.
Choosing South Carolina as an IRP base jurisdiction takes real property
S.C. Code Ann. 56-3-660(C) requires a motor carrier selecting South Carolina as its International Registration Plan base jurisdiction to own or lease real property used directly in the transportation of freight or persons within the State. That is a statutory requirement on top of the IRP plan's own established-place-of-business test, and SCDMV separately rules out virtual offices, PO boxes, shared rented addresses, flexible workplaces, mailbox stores, and internet-only companies.
Two agencies, two credentials, one dividing line
Since 2022 Act No. 214 amended S.C. Code Ann. 58-23-20, the Public Service Commission's motor carrier jurisdiction reaches only the transportation of persons, hazardous waste for disposal, and household goods for compensation. Everything else that hauls for hire inside South Carolina goes to SCDMV for a Certificate of Compliance, which SCDMV describes as a certificate representing an intrastate for-hire motor carrier that has complied with its safety and insurance requirements, issued to all intrastate for-hire carriers except passenger, household goods, and hazardous waste for disposal carriers.
The Transport Police, not the DMV, enforce the safety rules
The Transport Police Division of the South Carolina Department of Public Safety has exclusive authority in the State to enforce the commercial motor vehicle carrier laws, which include the Federal Motor Carrier Safety Regulations, the Hazardous Material Regulations, and the size and weight laws. SCDMV Form COC tells applicants to call the State Transport Police at (803) 896-5500 to find out which safety regulations apply to them, and SCDOT tells carriers to call the same unit at (803) 896-5500 for emergency clearance to bypass a weigh station.
IFTA decals are free and IFTA lives at the DMV
Most states put IFTA at a revenue or taxation department. South Carolina puts the licence, the decals, the quarterly returns, and the audit at SCDMV Motor Carrier Services, and charges nothing for the decals. New IFTA accounts can only be opened online, faxed applications are not accepted, and mail-in renewals must reach Blythewood by December 1 to guarantee credentials by December 31.
Police escorts start at 16 feet wide
A load wider than 16 feet needs one front and one rear civilian escort plus one front and one rear police escort on all roadways, unless the SCDOT Permit Director grants a written exception, and the escorting officers may require more. Below that, over 12 up to 14 feet needs one front escort only on two-lane highways, and over 14 up to 16 feet needs a front and a rear escort on all roadways. Any load 16 feet high or above needs a certified route survey filed before the permit issues plus a front escort with a height pole for the whole move.
The oversize fee schedule has not moved since 2012
SCDOT states on its own permit page that the fee schedule for an oversize or overweight permit was last revised July 1, 2012. The single trip and annual multiple trip prices have not moved since, which makes this one of the few permit costs a South Carolina carrier can budget against for years at a time. The current amounts are on the oversize and overweight page, each against the document that sets it.
Summer weekend closures on the coast
From Memorial Day through Labor Day, oversize and overweight movement is prohibited on Saturday and Sunday east of I-95 over routes including US-378, SC-327, US-76, SC-576, US-501, SC-22, SC-31, and SC-9 in the Myrtle Beach area, on US-17 from the North Carolina line south to Georgetown, and on any other routes in the Myrtle Beach vicinity. Carriers running the Charleston and Myrtle Beach corridors in summer lose both weekend days on those roads.
Farm and forest hauling sits outside the Commission entirely
Articles 1 to 11 of Chapter 23 do not apply to farmers or dairymen hauling dairy or farm products, to persons hauling agricultural livestock and poultry feeds, to other persons hauling perishable farm or dairy products for hire from the farm to the first market when sold in South Carolina, or to lumber haulers moving lumber from the forest to shipping points in the State. The Public Service Commission and the Office of Regulatory Staff also have no jurisdiction for safety purposes over persons transporting farm or forest products from the farm to the first market.
More South Carolina rules that catch carriers out
- State carrier number: detail
- South Carolina issues no general state carrier number to freight carriers. Carriers regulated by the Public Service Commission (passenger, household goods, and hazardous waste for disposal) display a PSC I.D. number in the form SCPSC #1234 alongside the company name on both sides of the vehicle, in letters and figures not less than three inches high. Certificate of Compliance holders get a certificate rather than a displayed number.
The permit office and Safehaul
SCDOT runs oversize and overweight permitting from a single office in Columbia, and every permit request is submitted online through Safehaul. A company account has to be set up before any order goes in, and SCDOT will hold an advance deposit in escrow so permits can be pulled without a payment step each time.
The office keeps weekday business hours and publishes an after-hours line for emergencies. Carriers who need clearance to bypass a weigh station in an emergency call the State Transport Police rather than the permit office.
The permit types South Carolina issues
Single trip permits cover one move over the legal limits, priced from a base fee with a width surcharge that steps up in brackets as the load gets wider. The annual multiple trip permit is the volume option: one yearly fee, auto-issued around the clock, covering repeated moves inside a published width, height, and weight envelope tied to a specific towing vehicle.
Past those two, South Carolina keeps a set of annual commodity permits. Cotton modular vehicles, sheet tobacco trucks, culvert pipe haulers, bulk agricultural loads including unprocessed forest products, and house movers each have their own permit with its own dimensions and travel rules. Road machinery, farm implements, fire apparatus, and timber equipment get a partial statutory exemption plus a permission permit with a small administrative charge.
Our South Carolina oversize and overweight page carries the full fee schedule, the escort thresholds, and the superload process.
Trip and fuel permits from SCDMV
The other permit door is registration and fuel tax. A carrier running an apportionable vehicle without IRP plates buys a short trip permit, and a carrier running a qualified vehicle without an IFTA licence or decals buys a fuel permit that runs several times longer. Both are set by regulation at the same price, and both are now sold directly by SCDMV rather than through a permit service.
First-time buyers have to be approved for the Motor Carrier Services portal before they can order, and that approval takes up to two days, which is not a lead time you want to discover on a Friday afternoon. Our South Carolina trip and fuel permits page carries the sourced fees, durations, and the trigger list.
When permitted loads cannot move
South Carolina publishes no city-by-city curfew list. The restriction is written into the travel-time rule itself, keyed to how wide the load is: most permitted loads run sunrise to sunset, wider ones lose the weekday commuter windows near large urban areas, and the widest are confined to a mid-day band that shrinks further on school days.
Six holidays close the road to permitted movement entirely, and the Permit Director may extend the block from midday before to midday after depending on route and dimensions. The coastal rule catches carriers out: from Memorial Day through Labor Day, oversize movement is prohibited on Saturdays and Sundays east of I-95 across a named list of Myrtle Beach and Grand Strand routes.
Compare beyond South Carolina
Running multi-state loads? The trucking permits by state table shows which permit families and issuing offices apply in every jurisdiction, the oversize permit costs by state table compares limits and fees across all 51 jurisdictions, and the permit cost estimator prices a specific load per state.
Frequently asked questions
Where do I apply for South Carolina truck permits?
- Oversize and overweight permits go through Safehaul, the SCDOT online permitting system, after your company account is set up. Trip and fuel permits go through the SCDMV Motor Carrier Services sign in portal, which needs its own approved login.
Does South Carolina offer an annual oversize permit?
- Yes. The multiple trip permit is auto-issued around the clock for non-divisible loads, mobile homes, and containerized cargo inside a published envelope, tied to one towing vehicle by VIN and tag and valid a year from issue. A route-specific version can be submitted for permit office review at greater height and weight.
Are there commodity-specific permits in South Carolina?
- Yes. Annual permits exist for cotton modular vehicles, sheet tobacco trucks, culvert pipe, bulk agricultural products including unprocessed forest products, and house moving. Road machinery, products of husbandry, farm implements, fire apparatus, and timber equipment carry a partial statutory exemption and a permission permit.
How long does a South Carolina trip permit last?
- Two different clocks. The registration trip permit for a carrier without apportioned plates runs a matter of hours, while the fuel permit for a carrier without an IFTA licence runs several days. Both durations and both prices are fixed by regulation and sit on our South Carolina trip and fuel permits page.
Haul Handbook publishes educational information about trucking registration and compliance requirements. This is not legal, financial, or tax advice. Rules, fees, and deadlines change; confirm with the agency before you file or pay.