How to become a licensed plumber in South Carolina

Licensing office South Carolina Residential Builders Commission and Contractor's Licensing Board (SC Department of Labor, Licensing and Regulation) · (803) 896-4696 [1][3]

The license pathway in South Carolina

1. 1

   Plumber working for a contractor (no state card)

   South Carolina has no apprentice or helper registration. The residential license is for independent contractors who contract with a builder, general contractor or property owner, and commercial licenses go to the contracting business. Your hours under a licensed plumber count toward a license later. [3][4][11]

2. 2

   Journeyman Plumber certification (CAGC)

   • 4,000 hours on the job
   • Yes: CAGC Foundation exam through PROV, online or in person
   • $35 application

   A certification formerly issued by the Municipal Association of South Carolina. You need 2 years (4,000 hours) of full-time plumbing installation experience under a journeyman or master; a two-year technical college degree counts as one year. It isn't a state license; ask your city or county whether it requires one. [2][4][8][9]

3. 3

   Residential Plumber license

   • 1 year of experience
   • Yes: Residential Plumbing (65 questions, 67.7% to pass, 180 minutes) plus Business Management and Law (50 questions), open book, PSI; $94 for both parts
   • $135 application, $220 license
   • Every 2 years by June 30 of odd years; $220

   Needed to contract for residential plumbing work over $500. The scope covers water and natural gas piping, sewage systems and water treatment systems common to homes. You need one year of residential plumbing experience within the past five years; jobs over $5,000 also need a $10,000 surety bond. [1][10][11][12][13][21]

4. 4

   Master Plumber certification (CAGC)

   • 8,000 hours on the job
   • Yes: CAGC Foundation exam through PROV
   • $35 application

   For certified journeymen with at least four years (8,000 hours) in the trade, two of them under a master. A Master Residential Plumber certification needs four years, two under a master. A master certification issued by exam lets you skip the technical exam for the state residential and commercial plumbing licenses. [1][8][14]

5. 5

   Mechanical Contractor: Plumbing classification (commercial)

   • 2 years of experience
   • Yes: Plumber exam (80 questions, 56 correct to pass, 4 hours, $75) plus Business Management and Law for Commercial Contractors ($75), open book, PSI
   • $350 initial license
   • Every 2 years (expires October 31 of odd years); $135

   Needed for commercial plumbing work over $10,000. The license belongs to the business, which names a Primary Qualifying Party (PQP) who passed the exams and has at least two years of full-time experience within the past five. The license group (1 to 5) sets the largest job, from $35,000 to unlimited. [3][5][14][15][16]

Who needs a license in South Carolina

South Carolina licenses plumbers at two levels, through two boards in the Department of Labor, Licensing and Regulation (LLR).

• Residential: state law defines a residential specialty contractor as "an independent contractor" who contracts with a licensed residential builder, general contractor or property owner when the job is over $500. Plumbers must get a specialty contractor license after passing the exam.
• Commercial: no business may do mechanical contracting (which includes plumbing) where the total cost of construction is over $10,000 without a license from the Contractor's Licensing Board.

A licensed mechanical contractor with the Plumbing classification doesn't also need the residential license for work in that classification. A residential builder licensed by exam may also do residential plumbing.

Recent change: a 2023 law (Act 69, H.4115) raised the commercial threshold from $5,000 to more than $10,000. The residential thresholds didn't change. [1][4][5][6][7]

No state journeyman license: what that means for you

There's no state apprentice, journeyman or master plumber license in South Carolina. You can learn the trade working for a contractor without a state card.

Plumbing certifications do exist. The Municipal Association of South Carolina ran this Mechanical Trades Certification Program from 1965 until January 1, 2026, when Carolinas AGC took it over. The CAGC Foundation says its card confirms you met its experience and exam requirements and shouldn't be confused with the state licenses.

• Journeyman Plumber: 2 years (4,000 hours) of full-time plumbing installation experience under a journeyman or master. A two-year degree from an accredited technical college counts as one year.
• Master Plumber: a certified journeyman with at least four years (8,000 hours) in the trade, two of them under a master. Ten documented years can replace the journeyman requirement.
• Master Residential Plumber: four years in the trade, at least two under a master.
• Journeyman Gasfitter and Journeyman Pipefitter certifications are also offered.

State law lets counties and cities examine and license residential specialty contractors, but not re-test someone who passed a Commission-approved exam. Ask your local building department what it requires. [2][4][8][9]

The residential plumber license

The Residential Builders Commission licenses residential plumbers. To qualify for the exam you need at least one year of residential plumbing experience within the past five years. Each supervisor or employer fills out an Experience Affidavit and must have been appropriately licensed while supervising you. Experience from any state or country counts.

The Residential Plumbing exam has 65 questions; you need 44 correct (67.7%) and get 180 minutes. You also pass the 50-question Business Management and Law exam (scale score 68). Both are open book at PSI, which charges $94 for both parts. Your eligibility lasts one year with three attempts.

After passing, you pay the $220 license fee. Licenses renew every two years by June 30 of odd-numbered years. State law (S.C. Code § 40-59-230) still says the Commission renews licenses annually, while the Commission's current FAQ (frequently asked questions) describes two-year renewals; confirm with the Commission. [1][4][10][11][12][13]

Commercial plumbing contractor license

Commercial licenses belong to the business. Each classification needs a Primary Qualifying Party (PQP) who passed the technical and business and law exams and has at least 2 years of work experience within the past 5 years in the classification.

The PSI Plumber exam has 80 questions; you need 56 correct and get 4 hours ($75). The Business Management and Law for Commercial Contractors exam takes 125 minutes ($75). Commercial exams are open book, and no pre-approval is needed to book them.

The license group sets the most you can bid on one job: Group 1 $35,000, Group 2 $100,000, Group 3 $200,000, Group 4 $400,000 and Group 5 unlimited. The initial license fee is $350; mechanical contractor licenses expire October 31 of odd-numbered years and renew for $135. [3][5][14][15][16]

Union and open-shop apprenticeships

UA Local 421 represents plumbers, pipefitters, welders and HVAC-R (heating, ventilation, air conditioning and refrigeration) service techs in North and South Carolina. Its training arm, Mechanical Trades Carolina, runs four training centers, including one in North Charleston. Applicants need a high school diploma or GED, a North or South Carolina driver's license and residence, and an ACT (ACT college admissions test) Career Readiness Certificate at Silver or higher.

Apprenticeship Carolina, part of the SC Technical College System, helps employers register apprenticeships. Registered apprentices are paid, get at least one guaranteed raise and earn a Journeyworker credential from the U.S. Department of Labor when they finish.

For the differences between routes, see union vs. non-union, how to get an apprenticeship and helper jobs. [17][18][19]

If you're licensed in another state

Residential: the Commission waives the technical exam if you hold a North Carolina or Mississippi license obtained by exam for at least a year, or an SC master plumber certification by exam. You still need the experience and the Business Management and Law exam.

Commercial: the Board's exam waiver list (as of May 2026) accepts North Carolina Plumbing Class 1, Ohio Plumbing and Tennessee CMC/Mechanical or CMC-A exams for the Plumbing classification. You must pass the SC business and law exam, and licenses obtained by waiver or grandfathering don't qualify.

See our license reciprocity guide and reciprocity map. [1][12][14][20]

Steps to get licensed in South Carolina

1. Get hired and document your experience

   Work for a licensed plumbing contractor or in an apprenticeship. Keep W-2s or 1099s and the names of your licensed supervisors; the Commission verifies experience through affidavits they complete. [10][11]

2. Consider a journeyman certification

   After 2 years (4,000 hours) under a journeyman or master, you can apply for the CAGC Journeyman Plumber certification ($35) through the CAGC Foundation. [2][8]

3. Apply for the residential plumber license

   With one year of residential plumbing experience in the past five years, apply on the Commission's residential plumber page with the $135 application fee. Experience must be approved before you can test. [1][10]

4. Pass both PSI exams

   After approval you have one year and three attempts to pass the Residential Plumbing exam and the Business Management and Law exam, booked through PSI. Fail three times and you wait 12 months. [4][11]

5. Get licensed and renew

   Send your PSI results and the $220 license fee (plus a $10,000 bond if you'll take jobs over $5,000). The license renews every two years by June 30 of odd-numbered years. [11][21]

6. For commercial work, qualify a mechanical contractor license

   With 2 years of experience in the past 5, pass the PSI Plumber and commercial business and law exams, then apply to the Contractor's Licensing Board with the $350 fee and a financial statement or bond for your license group. [14][15][16]

Where to get the hours

Programs that train plumbers in or for South Carolina, from their own official pages. Listed by type, not ranked.

• Union

  UA Local 421 apprenticeship (Mechanical Trades Carolina)

  The union for plumbers, pipefitters, welders and HVAC-R service techs in the Carolinas. Its training arm, Mechanical Trades Carolina, has four training centers, including North Charleston. Local 421 also takes pre-apprenticeship applications. [17][18]

• State program

  Apprenticeship Carolina registered apprenticeships

  Apprenticeship Carolina, a division of the SC Technical College System, helps employers register apprenticeships. You apply to and are hired by the employer; programs typically last one to four years. [19]

Licensed in another state?

Questions people ask