The Law and Business Exam: A C-10 Study Guide
Skilled electricians walk into the C-10 process thinking the hard part is the trade exam. Load calcs, conductor sizing, grounding — that's the stuff you sweat over. Then the Law and Business exam quietly takes people down. It's a separate test, and it has nothing to do with whether you can bend pipe or read Table 310.16 for conductor ampacity. It's about running a licensed business in California without getting sued, fined, or disciplined by the board.
Here's the reframe that helps: this exam isn't checking whether you're a good electrician. It's checking whether you're a safe contractor — someone who won't take a bad deposit, botch a lien, or skip workers' comp. If you've only ever worked as an employee, a lot of this is genuinely new. That's why it ambushes people.
Two exams, one license
To get licensed you pass both a trade exam and the Law and Business exam. They're taken at the testing center, often the same day. The trade portion is covered in what's actually on the C-10 exam; this guide is strictly the law side. Both are multiple choice, and the format and passing score work the same way for each. Miss one, and you retest just that portion — but you're not licensed until both are done.
The Law and Business exam is shared across all trades. A C-10 electrician and a B general contractor sit for the same law test. None of the questions reference the electrical code. Every one is about contracts, money, employees, safety, and how the CSLB regulates licensees.
The big content buckets
The board publishes an exam outline, and the weighting shifts over time, so pull the current version from cslb.ca.gov. Broadly, the material breaks into these areas:
| Area | What it actually covers |
|---|---|
| Business organization & licensing | Sole prop vs. corp vs. LLC, RMO/RME rules, license classifications, name styles |
| Contracts & change orders | Required contract terms, home-improvement rules, down-payment limits, cancellation rights |
| Employment & payroll | Workers' comp, prevailing wage, payroll taxes, employee vs. independent contractor |
| Safety | Cal/OSHA, the IIPP, hazard rules, recordkeeping |
| Financial management | Bonds, insurance, liens, basic bookkeeping, cash flow |
| Public works & bidding | Prevailing wage, DIR registration, bid bonds |
Notice how little of this a typical journeyman deals with day to day. That's the gap you're closing.
Contracts and change orders
This is the heaviest-hit area, and the rules are specific. For home-improvement contracts — most residential electrical work — California caps the down payment at $500 or 10% of the contract price, whichever is less. Not 10% flat. Not "whatever the customer agrees to." The lesser of the two. Test writers love that distinction.
You also need the three-day right to cancel on home-improvement contracts (longer for certain senior or disaster situations), the rule that the contract must be in writing and signed before work starts, and that change orders must be written and signed too. A verbal "yeah, add the sub-panel" that you never document is exactly the kind of thing the exam — and real disciplinary cases — punish.
Know the difference between a progress payment and a down payment, and that you can't collect for work or materials beyond what the contract's payment schedule allows.
Mechanics liens — memorize the clock
If a customer doesn't pay, a mechanics lien is your leverage. The exam tests the sequence and the deadlines, because a missed deadline kills the lien.
The chain runs like this: serve a preliminary notice (the 20-day notice) within 20 days of first furnishing labor or materials. If you're not paid, you record the mechanics lien within a set window after the work wraps, then you have a limited period to file a foreclosure lawsuit or the lien expires. Learn which action goes with which number of days. Also know who the preliminary notice must reach — owner, direct contractor, and construction lender if there is one.
Don't confuse a mechanics lien (private property) with a stop payment notice (which reaches construction funds) or a payment bond claim (public works). The exam will offer all three as answer choices on the same question.
Payroll, workers' comp, and prevailing wage
If you'll have employees, you owe workers' compensation insurance — full stop. The exam wants you to know it's mandatory the moment you have even one employee, and that misclassifying a worker as an independent contractor to dodge it is a serious violation.
For public works, prevailing wage kicks in. You register with the DIR, pay the published rate for the classification, and keep certified payroll records. Candidates who've only done private residential work often have never touched any of this, so give it real study time.
Understand payroll tax basics too: the difference between what you withhold and what you owe as the employer, and that unpaid payroll taxes are one of the fastest ways to lose a business.
Safety and Cal/OSHA
California runs its own OSHA. The single most tested item here is the Injury and Illness Prevention Program (IIPP) — every California employer must have one, in writing. Know that it's required, that it must be written, and roughly what it contains: someone responsible, hazard identification, correction procedures, training, and recordkeeping.
Beyond the IIPP, expect questions on reporting serious injuries to Cal/OSHA within the required timeframe, keeping the injury log, and general hazard-communication duties. This is employer safety law, not the code-based safety you study in grounding and bonding or GFCI and AFCI protection.
Bonding, insurance, and licensing rules
Every active California contractor posts a contractor's license bond. The exam expects you to know the bond exists, who it protects (the public, and in some cases employees for unpaid wages), and that it's not the same as liability insurance or workers' comp. The exact bond amount and the license fees change periodically, so confirm the current numbers at the CSLB rather than trusting an old figure — the full breakdown lives in our guide to C-10 bond and insurance requirements.
You'll also see questions on the RMO/RME structure (the qualifying person for a business), grounds for license discipline, and the rule that unlicensed contracting or exceeding your classification is a violation. If you're still sorting out the licensing path itself, the C-10 requirements checklist and the step-by-step guide to getting licensed fill in the surrounding process.
How to actually study this
Treat the law exam as its own subject, not an afterthought you cram the night before. The vocabulary is unfamiliar and the deadlines are precise, which is exactly the kind of material that rewards spaced repetition. Read the CSLB study guide, then drill the deadlines and dollar limits until they're automatic. Working practice questions under a timer is how the numbers stick and how you find the gaps before test day.
These concepts are here to help you study — the current CSLB publications and California law always govern. Confirm anything that carries a dollar amount or a deadline against the current source before you rely on it in the field.
Give the law exam the respect it deserves and it stops being an ambush. It becomes the easy half.