South Carolina Electrical Exam: Commercial vs. Residential (2026)

South Carolina has two electrical exams, both open book at PSI test centers. The commercial exam is 80 questions on the 2020 National Electrical Code (NEC), and you need 56 right in 5 hours. The residential exam is 60 questions on the 2017 NEC, and you need 44 right in 3 hours. Each also needs a business and law exam.

Which South Carolina electrical exam do you take?

• Commercial work over $10,000: a Mechanical Contractor license with the Electrical classification, from the SC Contractor's Licensing Board. You take the Electrician exam.
• Residential work over $500: a Residential Electrician license from the SC Residential Builders Commission. You take the Residential Electrical exam.

Experience rules and the application are in JCR's South Carolina license guide.

SC electrical contractor exam: what's on the commercial test?

The PSI Commercial Contractor bulletin (updated August 27, 2026) splits the 80 scored questions this way. Unscored trial questions may be added, with extra time.

• 45 questions, 9 each:
  • General electrical knowledge
  • Services, feeders and branch circuits
  • Grounding and bonding
  • Conductors and cables
  • Raceways and boxes
• 22 questions: safety (8), motors (7), electrical power (7)
• 13 questions:
  • Lighting (5)
  • Special occupancies, low voltage, illuminated signs and fire alarm (2 each)

The NASCLA electrical contractor exam is an alternative: 100 questions, 75 to pass, 270 minutes, $116, on the 2020 or 2023 NEC. Its book list is longer, so read JCR's NASCLA exam guide first.

SC residential electrician exam: what's on the residential test?

The PSI Residential Builders bulletin (updated October 9, 2026) covers homes up to 3 stories and up to 16 units.

• Services, feeders and branch circuits: 15 questions
• General electrical knowledge: 13, including voltage drop, blueprints and take-offs
• Grounding and bonding: 6, including grounding conductor table lookups
• Overcurrent, conductors and cables: 5 each
• Raceways and boxes, lighting, pools/garages/generators, safety: 4 each

The NASCLA residential electrical exam is an alternative: 100 questions, 70 to pass, 270 minutes, $116.

What can you bring into the South Carolina electrical license test?

PSI hands out no books, so bring these editions.

Commercial Electrician:

• The 2020 NEC plus South Carolina's code modifications (or the 2020 Handbook)
• NFPA 72, 2019 edition
• American Electricians' Handbook, 17th edition
• OSHA 29 CFR 1926, a Key Word Index for the 2020 NEC, and the SC 811 Excavator Manual

Residential Electrical:

• The 2017 NEC (or NEC Handbook)
• The SC version of the IRC, the 2018 IRC or the IRC Commentary
• Ugly's Electrical References (2017) and OSHA 29 CFR 1926

Book and calculator rules:

• Highlighting, underlining and indexing are fine. No handwriting or added papers.
• Tabs must be permanent: they tear the page if pulled. Peel-off tabs are removed. On the commercial exam, so are tab paper inserts.
• Calculators: silent, battery-powered, non-programmable, no letter keys.

How do booking, fees and retakes work?

• Commercial: book online at PSI's SC contractor page or by phone, $78 per attempt. You can't retake an exam you passed.
• Two dates: PSI caps testing at 6 hours a day. The 5-hour Electrician exam and 125-minute business exam need separate days.
• Residential: your eligibility letter lasts 1 year. Fail 3 times, and you wait 12 months from your last attempt.
• Test centers: Greenville, Columbia, North Charleston, Beaufort, Myrtle Beach and Charlotte, NC.
• Cancel at least 2 days out to keep your fee (by Saturday for a Monday exam).
• Arrive 30 minutes early with a photo ID that matches your registration.
• Results show on screen. A fail comes with a report of your weak areas.

How to pass the South Carolina electrical exam

• Know your pace: about 3¾ minutes a question commercial, 3 residential.
• Study the right edition. Answers are graded on the bulletin's edition, even if you bring a newer book.
• Follow the weights. Five core areas carry 45 of the 80 commercial points. Fire alarm is worth 2.
• Skip and come back. PSI lets you return to any question before time runs out.
• Study in short sessions. PSI's residential bulletin suggests 45 to 60 minutes at a time. Plan on 6–8 weeks, about an hour a night.

South Carolina electrical exam questions

What NEC edition is on the SC electrical exam?

Commercial uses the 2020 NEC with South Carolina's changes. Residential uses the 2017 NEC. The NASCLA versions allow the 2020 or 2023 NEC.

How many times can I take the SC electrical contractor exam?

Twice in 12 months, then once every 6 months. The business and law exam has no such limit within 12 months. Residential candidates get 3 attempts in their 12-month eligibility.

What score do I need on the SC residential electrician exam?

You need 44 of 60 correct (73.3%), though PSI says that can change as it reviews results. The residential business exam needs 34 of 50.

Do I need approval before I schedule the South Carolina electrical license test?

Only for residential, which needs an eligibility letter from the Residential Builders Commission first. Commercial candidates book PSI right away and apply to the Licensing Board after passing.