Class A
The combination license.
- One run
- 50 questions
- To pass
- 40 of 50
South Carolina runs commercial driver licensing through its own Department of Motor Vehicles. A good share of the commercial driving work in the state connects back to the Port of Charleston, one of the busier container ports on the East Coast, which means a meaningful part of local CDL demand is freight moving inland from the docks rather than long-haul through-traffic alone.
Every figure below names the document it came from, so you can check it rather than take our word for it.
Fees change without notice, so we do not repeat them here. Check South Carolina Department of Motor Vehicles for the current cost.
The knowledge tests are set by federal rule, so the questions are the same wherever you sit them. What changes is the paperwork above.
The combination license.
The heavy straight vehicle license. Group B covers a single vehicle rating 26,001 pounds or more, or one towing a unit of 10,000 pounds or less.
The small vehicle license.
The knowledge test every commercial driver takes, whatever class or endorsement they are after.
Required before you may drive any commercial vehicle with air brakes.
Required for a Class A license. Coupling and uncoupling, off-tracking, trailer brakes and the handling of a vehicle that is jointed in the middle.
The H endorsement. Placarding, shipping papers, loading and segregation rules, and what to do when something leaks.
The N endorsement. Surge, baffles, bulkheads, high center of gravity and the way a part-full tank changes how a vehicle stops and turns.
The T endorsement. Coupling and uncoupling multiple trailers, converter dollies, crack-the-whip and the inspection points a second trailer adds.
The P endorsement. Pre-trip and post-trip checks on a bus, loading and unloading, standee lines, and handling passengers on the road.
The S endorsement, taken alongside the passenger endorsement. Danger zones, mirror adjustment, loading and unloading students, and railroad crossings.
A study drill for the pre-trip inspection.
Interstates 95, 26 and 20 between them carry most of the state's commercial traffic, running along the coast and cutting inland toward Columbia and beyond. That concentrates both freight movement and testing demand along a fairly small number of routes, rather than spreading it evenly across the state the way it would in somewhere larger or less port-dependent. It is worth knowing which corridor you are near when you are looking for a test slot, since offices along the I-95 and I-26 routes tend to be busier than ones further off the main lines.
None of that changes what is on the exam. The knowledge tests, the pass mark and the age limits are all set in 49 CFR Part 383 and read the same in every state. You need 80 percent correct on each section to pass — a federal minimum, not something South Carolina decided for itself. You can drive commercially within South Carolina from 18; work that crosses into North Carolina or Georgia needs you to be 21.
General knowledge comes first for every applicant. What comes next depends on the vehicle you intend to drive. Failing the air brakes exam does not block your license — it attaches a restriction ruling out anything fitted with them, worth bearing in mind given how much of the state's freight moves in and out of the port on heavier equipment. Trailers over ten thousand pounds require the combination vehicles exam as well. The endorsements — tank, doubles and triples, hazardous materials, passenger, school bus — apply only where the work calls for them.
The hazardous materials endorsement is the one to plan around early: on top of the written exam it needs a Transportation Security Administration background check, run on a federal timeline separate from anything the SCDMV controls, so start it before you get to the last of the written exams rather than after.
Getting a commercial learner permit comes first, and federal rule requires a 14-day hold on it before a skills test can follow. The smart move is sitting your knowledge exams as soon as the permit is in hand, since a failed section is far easier to fix with weeks left on the permit than with none.
This site leaves fees out on purpose. South Carolina reviews and adjusts them periodically, and an old number printed here would be more misleading than useful, so the SCDMV is the place to check before you go. What we can offer instead is the content of the exams themselves — which questions come up, and precisely where each answer is sourced from.
Every question on every one of these is free, and each answer names the handbook page it came from.
Every question names the handbook, section and page it was read from, so you can check the answer instead of taking our word for it.
How we write these