What experience do I need for a California C-10 license?

The CSLB requires four years of journey-level electrical experience within the last ten years, verified by a qualified certifier such as a licensed C-10 contractor, employer, supervisor, or fellow journeyman. Technical training counts for up to three of the four years: an accredited electrical apprenticeship or a degree in electrical engineering or electrical technology can substitute, but you still need at least one year of hands-on journey-level work.

Is a C-10 license the same as an electrician certification?

No, and this trips up most applicants. The C-10 is a contractor license issued by the CSLB that lets you bid, contract, and pull permits. Electrician certification is a separate credential issued by the Division of Labor Standards Enforcement (DLSE) under Labor Code 3099 for people performing the work as employees. Many C-10 holders carry both.

How many exams do I take for the C-10?

Two. The Law & Business exam covers contracts, mechanics liens, employment rules, safety, insurance, bonds, and financial management. The C-10 Electrical trade exam covers the electrical scope itself. Each is computer-based, roughly 115 to 125 multiple-choice questions, 3.5 hours long, with a passing mark around 72 percent.

Which code does the C-10 trade exam test?

The California Electrical Code, which is Title 24 Part 3 and adopts the National Electrical Code with California amendments. Expect questions on grounding and bonding, overcurrent protection, conductor ampacity and derating, box fill, raceway sizing, motor and transformer circuits, load calculations, and Title 24 energy requirements for lighting controls.

What can a C-10 contractor legally do in California?

Under CCR Title 16 section 832.10, a C-10 contractor places, installs, erects, or connects electrical wires, fixtures, appliances, apparatus, raceways, conduit, and any part that generates, transmits, transforms, or utilizes electrical energy. It does not authorize you to run unrelated trades on the same job, that is a Class B General Building scope question.

What does the C-10 license cost and what bond is required?

The application fee is $450, the initial license fee is $200, and a $25,000 contractor bond is required before the license goes active. If you qualify through a responsible managing employee or officer rather than as a sole owner, a $25,000 bond of qualifying individual may also apply. Workers' compensation coverage is mandatory for C-10 regardless of employee count.

How long should I study for the C-10 exams?

Most candidates need 60 to 100 hours over six to ten weeks. Field electricians usually clear the trade exam faster and struggle with Law & Business; candidates coming from an office or estimating role tend to see the reverse. Timed practice exams scoped to the C-10 blueprint are the strongest predictor of a first-attempt pass.

California C10 License: Requirements & Exam Guide

What the C-10 classification covers

The C-10 Electrical classification is defined in California Code of Regulations Title 16 section 832.10. A C-10 contractor places, installs, erects, or connects electrical wires, fixtures, appliances, apparatus, raceways, conduit, and any part of a system that generates, transmits, transforms, or utilizes electrical energy in any form for light, heat, power, or communication. In practice that is service upgrades, panel changes, branch circuits, lighting, motor controls, EV chargers, solar interconnections, and low-voltage systems where electrical work is the fundamental scope.

The boundary that matters most: the C-10 does not let you take on unrelated trades on the same contract. If a job involves two or more unrelated trades with framing or carpentry as a component, that is Class B General Building territory. Many electrical contractors eventually carry both, and a C-10 plus a C-46 Solar is one of the most common two-classification combinations in California.

C-10 experience requirements

The CSLB wants four years of journey-level or higher electrical experience gained within the last ten years. Journey-level means you performed the work without supervision at the skill level of a fully qualified electrician, apprentice hours do not count as journey-level time. Your experience is verified on the certification page of the application by someone with direct knowledge of your work: a licensed C-10 contractor, an employer, a supervisor, a fellow journeyman, a building inspector, or a union representative.

Technical education can substitute for up to three of the four years. A completed state-approved electrical apprenticeship, an associate degree in electrical technology, or a bachelor's degree in electrical engineering all shorten the requirement, but the CSLB still requires at least one year of practical journey-level work no matter how much schooling you bring.

One distinction to keep straight before you apply: the C-10 contractor license and state electrician certification are different credentials. Certification under Labor Code 3099 is administered by the Division of Labor Standards Enforcement and applies to individuals performing electrical work as employees. The C-10 is the CSLB license that lets you contract, bid, and pull permits. C-10 contractors who employ electricians must ensure those employees are certified or enrolled in an approved apprenticeship.

The two-part exam structure

Every C-10 candidate sits for two separate computer-based exams at a CSLB testing area. Both are multiple choice, roughly 115 to 125 questions, 3.5 hours each, and both must be passed at about 72 percent within 18 months of application approval.

Part 1: Law & Business

This is the shared exam every classification takes, and it is where a large share of skilled electricians get stopped. The content outline covers business organization and licensing, contracts and mechanics lien law, employment requirements, public works, safety, insurance and bonds, and financial management. Nothing on it is electrical. Expect questions on the $500 threshold that triggers the license requirement, the 20-day preliminary notice and 90-day mechanics lien deadline, home improvement contract down payment limits, the $25,000 bond, workers' compensation obligations, and Cal/OSHA reporting duties. Our business law guide covers this material in the order the exam tests it.

Part 2: C-10 Electrical trade exam

The trade exam is built on the California Electrical Code, Title 24 Part 3, which adopts the National Electrical Code with California amendments. The heaviest-weighted areas are consistently:

Grounding and bonding. Grounding electrode systems, equipment grounding conductor sizing, bonding of metallic piping and structural steel, separately derived systems, and the difference between a grounded conductor and a grounding conductor. Table-based sizing questions are common.
Overcurrent protection. Breaker and fuse selection, conductor protection at the point of supply, tap rules, series ratings, and the specific allowances for motor and transformer circuits, where the overcurrent device protects the equipment rather than the conductor.
Conductor ampacity and derating. Ampacity tables, ambient temperature correction, conduit fill and more-than-three-current-carrying-conductor adjustment, termination temperature limits, and voltage drop on long runs.
Raceway, box, and enclosure sizing. Conduit fill percentages, box fill counts, pull and junction box dimensions, support and securement spacing, and wet-location and hazardous-location requirements.
Load calculations. Dwelling unit service and feeder calculations, general lighting loads, demand factors for ranges and dryers, continuous versus noncontinuous loads, and service sizing for commercial occupancies.
Branch circuits and protection devices. GFCI and AFCI locations, receptacle spacing, dedicated circuits, and required disconnecting means.
Title 24 energy requirements. California-specific lighting controls, occupancy sensing, daylighting, and EV-capable and solar-ready provisions that do not appear in the base NEC.
Planning, estimating, and safety. Reading plans and one-line diagrams, material takeoffs, lockout/tagout, arc-flash and PPE requirements, and confined-space and ladder safety.

The single most common cause of missed questions is table navigation under time pressure. You cannot bring the code book into the room, so the working knowledge has to be memorized: which table governs which sizing decision, and which correction factors stack.

Bond, insurance, and fees

$450 application fee, submitted with the Application for Original Contractor License.
$200 initial license fee once both exams are passed.
$25,000 contractor bond filed with the CSLB before the license is issued.
$25,000 bond of qualifying individual when you qualify through an RME or a non-owning RMO.
Workers' compensation coverage, which C-10 requires even with no employees, unlike most classifications where a signed exemption is allowed.
$100 rescheduling fee per exam retake, with a 21-day wait between attempts.

Our full cost breakdown walks through the total out-of-pocket including fingerprinting and renewal.

How to prep for the C-10

Most C-10 candidates need 60 to 100 hours over six to ten weeks. Split the plan by weakness rather than by exam order. Field electricians usually clear the trade content in half the time and then lose a month to lien law and financial management. Candidates from an estimating or office background see the opposite pattern and need drilling on grounding, derating, and load calculations.

Study the Law & Business material first because it is shared, then move into C-10 trade content aligned to the CSLB blueprint. Take timed, full-length practice exams from week two onward, not just at the end, so scoring trends tell you when you are actually ready rather than when you feel ready.

Our course keeps C-10 content scoped to the C-10 classification: practice questions written against California Electrical Code sections, lessons on each blueprint domain, an AI tutor that answers in the context of your license class, and a Pass Probability score based on your recent timed attempts. Start with the free readiness test to see where you stand, or review the course details.

The California C-10 Electrical Contractor License