CDL Permit Test in South Carolina: Tests, Fees, and Documents

The CDL permit test in South Carolina is a written knowledge exam you take at an SCDMV branch to earn a Commercial Learner’s Permit, which is the first step toward a full commercial driver’s license. You must score at least 80 percent on the General Knowledge test, plus any additional tests tied to the class of vehicle you plan to drive. Total cost runs around $20, the permit is good for one year, and you have to hold it for at least 14 days before taking the behind-the-wheel skills test.

Who Can Apply

You must be at least 18 years old and already hold a valid South Carolina Class D driver’s license before the SCDMV will issue a CLP.1South Carolina Legislature. South Carolina Code 56-1-2080 – Qualifications for Commercial Driver License At 18, you can only drive commercial vehicles inside South Carolina. Federal rules require you to be 21 to cross state lines for work.2eCFR. 49 CFR 383.25 – Commercial Learner’s Permit

Your license cannot be suspended, revoked, or canceled in any state, and you cannot hold a CDL from another state. If you do hold one elsewhere, you’ll have to surrender it before South Carolina issues your CLP.1South Carolina Legislature. South Carolina Code 56-1-2080 – Qualifications for Commercial Driver License

Which Tests You’ll Take

How many tests you sit for depends on the CDL class you’re pursuing. South Carolina follows the national three-class system:

  • Class A covers any combination of vehicles with a gross combination weight rating of 26,001 pounds or more, where the towed vehicle weighs more than 10,000 pounds. Tractor-trailers fall here.
  • Class B covers any single vehicle rated 26,001 pounds or more, or one towing a vehicle up to 10,000 pounds. Dump trucks, large buses, and box trucks fall here.
  • Class C covers vehicles that don’t qualify as A or B but either carry 16 or more passengers (including the driver) or display a hazmat placard.

Class A is the broadest license and lets you operate Class B and C vehicles as well.3SCDMV. Classes A, B, and C

Every applicant takes the General Knowledge test. If your future vehicle has air brakes (most large commercial vehicles do), add the Air Brakes test. If you’re going for Class A, you also have to pass the Combination Vehicles test; without it, you can’t get a Class A CLP at all.

What’s on Each Knowledge Test

The exams are built around federal standards in 49 CFR § 383.111, which require every state to test the same core knowledge areas.4eCFR. 49 CFR 383.111 – Required Knowledge South Carolina’s Commercial Driver License Manual is the official study guide, free to download from the SCDMV website.5South Carolina Department of Motor Vehicles. Commercial Driver License Manual

General Knowledge

This is the largest test and the one everyone takes. It covers vehicle inspection procedures, cargo securement, speed and space management, driving in bad weather and at night, shifting, backing, emergency procedures, and the driver-related parts of federal safety regulations. The manual spells out specific braking distances, weight limits, and vehicle dimensions that show up as test questions, so give this one the most study time.

Air Brakes

The Air Brakes test covers how compressors, storage tanks, and brake chambers work together, what the gauges and warning signals mean, and how to handle the longer stopping distances and brake lag of air systems compared with hydraulic ones. Skip this test and your CLP gets an “L” restriction, which bars you from operating any vehicle with air brakes.

Combination Vehicles

Required for Class A, this section covers coupling and uncoupling trailers, the rollover risks of articulated vehicles, and how to recognize and prevent jackknifing.

Endorsement Tests You Can Add at the Permit Stage

Certain cargo and passenger types require endorsements. You can take some endorsement knowledge tests while applying for your CLP, though what you can actually do with them is limited until you earn the full CDL. Federal rules allow only three endorsements on a CLP: Passenger (P), School Bus (S), and Tank Vehicle (N).2eCFR. 49 CFR 383.25 – Commercial Learner’s Permit

  • Passenger (P): required to carry 16 or more passengers. On a CLP you can only have trainees, examiners, auditors, and your supervising CDL holder in the vehicle.
  • School Bus (S): same testing and restrictions as the P endorsement, specific to school buses. No students on board with a CLP.
  • Tank Vehicle (N): required for transporting liquids or gases in bulk tanks. With a CLP, you can only operate empty tank vehicles that have been purged of hazardous residue.

Hazardous Materials (H) and Doubles/Triples (T) cannot be placed on a CLP at all; both wait until you apply for the full CDL. The H endorsement also requires a TSA security threat assessment, which costs $85.25 as of 2025, or $41 if you already hold a valid TWIC card.6Transportation Security Administration. HAZMAT Endorsement

Passing Score and Retests

You need at least 80 percent correct on each knowledge test you attempt.7Legal Information Institute. South Carolina Code Regs 38-383.135 – Minimum Passing Scores That threshold applies to every test separately. Passing General Knowledge with flying colors won’t help you if you score 75 percent on Air Brakes.

Tests run on computer terminals and score as you go, so you know your result immediately. Fail a test on your first try and you can usually retest fairly quickly. After a second failure on the same test, you wait seven calendar days. A third or subsequent failure means a 30-day wait before you can try again.8South Carolina Department of Motor Vehicles. CDL Testing Studying the manual thoroughly before your first visit saves real time.

Documents to Bring

You’ll complete SCDMV Form 447-CDL, the application for a Commercial Learner’s Permit or CDL. It asks for personal information, driving history, insurance details, and a declaration that you meet federal qualification requirements under 49 CFR Part 391. Falsifying anything on the application can trigger a 60-day disqualification and possible criminal prosecution.

Bring original documents that prove three things:

  • Identity and citizenship: a birth certificate with a registrar’s signature, a current or recently expired U.S. passport, or a certificate of naturalization.
  • Social Security number: your Social Security card, a W-2, or a military ID showing the number.
  • South Carolina residency: a current utility bill, mortgage document, or employment record dated within the past 90 days.

The full document checklist is on SCDMV Form MV-93 for U.S. citizens or Form MV-94 for international applicants. A standard CLP will be printed with “NOT FOR FEDERAL I.D.” on the front, which doesn’t affect commercial driving but won’t work for things like boarding a domestic flight.

Medical Certification

Every applicant must self-certify into one of four federal operation categories: interstate non-excepted, interstate excepted, intrastate non-excepted, or intrastate excepted.9Federal Motor Carrier Safety Administration. Medical Requirements Which category you pick determines whether you need a federal DOT medical card or only South Carolina’s state medical requirements.

Most new applicants land in the non-excepted categories, which means you need a Medical Examiner’s Certificate (Form MCSA-5876) from a physical performed by a provider on the FMCSA’s National Registry of Certified Medical Examiners.10Federal Motor Carrier Safety Administration. Medical Examiner’s Certificate (MEC), Form MCSA-5876 The exam screens for conditions that make commercial driving unsafe, like uncontrolled high blood pressure, vision problems, or seizure disorders. Keep this certificate current with the SCDMV. If it lapses, the agency can downgrade your commercial license to a standard Class D.

Fees

The CLP breaks down into three charges:

  • Application fee: $15, one-time, due at testing.
  • Knowledge tests: $2 each. General Knowledge, Air Brakes, Combination Vehicles, and any endorsement tests all cost $2 apiece.
  • CLP card: $2.50.

A Class A applicant taking General Knowledge, Air Brakes, and Combination Vehicles pays $23.50 total. A Class B applicant taking only General Knowledge and Air Brakes pays $21.50.11SCDMV. Getting Your First CDL

What Your CLP Lets You Do

Once you pass and pay, the SCDMV issues your CLP with a one-year expiration date.11SCDMV. Getting Your First CDL During that year, strict rules govern how you can use it:

  • A licensed CDL holder with the correct class and endorsements must sit in the front passenger seat (or directly behind the driver in a passenger vehicle) any time you drive on public roads.
  • You cannot transport hazardous materials requiring placards, period.
  • You must carry your South Carolina Class D license alongside your CLP whenever you drive.
  • You cannot take the CDL skills test until at least 14 calendar days after the CLP was issued.2eCFR. 49 CFR 383.25 – Commercial Learner’s Permit

Testing on a vehicle with an automatic transmission adds an “E” restriction that limits you to automatics. Skipping Air Brakes adds the “L” restriction. Both restrictions carry over to your CDL unless you later test without them.

If your CLP expires before you pass the skills test, you have to retake and pass every applicable knowledge test to get a new one.11SCDMV. Getting Your First CDL A year sounds like plenty of time, but between CDL school, work, and scheduling the skills exam it goes by faster than most people expect.