- Core Trades is 30% of the exam - the single heaviest domain, covering plumbing, electrical, HVAC, and more.
- The trade exam is 115 questions in 210 minutes, closed book, four choices, no penalty for guessing.
- Original application costs $450; a reschedule or retake costs $100; you must wait 21 days after a fail.
- You need four years of journeyman-level experience in the last 10 years plus a $25,000 surety bond.
Quick Facts Snapshot
Bookmark this page. It's built as a single-page reference you can scan the night before test day, not another long-form explainer. If you need the full walkthrough behind any of these facts, the GC License Study Guide 2026 covers preparation strategy in depth and the GC License Requirements 2026 page breaks down eligibility line by line.
| Item | Detail |
|---|---|
| Issuing body | California Contractors State License Board (CSLB), under Business and Professions Code §7000 et seq. |
| Exam administrator | PSI Services LLC, under contract to CSLB |
| Required exams | Law and Business (all classifications) + Class B General Building trade exam |
| Trade exam length | 115 questions, 210 minutes, closed book, calculator provided |
| Application fee | $450, non-refundable (first-sitting exam fees are bundled in) |
| License fee | $200 (sole owner) / $350 (corp, partnership, JV, LLC) |
| Reschedule/retake fee | $100 |
| Experience requirement | 4 years journeyman-level in last 10 years (degree substitutes up to 3 years) |
| Bond | $25,000 contractor license surety bond |
| Application validity | 18 months from acceptance |
| Renewal cycle | Every 2 years |
The Five Domains at a Glance
The Class B trade exam is built from five content areas. If you only have time to memorize one thing before test day, memorize these five names and their weights - they determine where your study hours should go. For a deeper dive into what each domain actually tests, see the GC License Exam Domains 2026 guide.
Domain 1: Planning and Estimating (15%)
Covers reading plans and specs, takeoffs, bidding, scheduling, and contract documents.
- Blueprint and specification interpretation
- Cost estimating and material quantity takeoffs
Domain 2: Framing and Structural Components (20%)
Covers structural systems from foundation to roof framing.
- Wood and steel framing methods
- Foundations, footings, and structural connections
Domain 3: Core Trades (30%) - the heaviest block
Spans plumbing, electrical, HVAC, concrete, earthwork and surveying, insulation, acoustical and weatherproofing, and roofing. Because it's nearly a third of the exam, weak spots here have an outsized impact on your score.
- Rough-in and system coordination across trades
- Concrete, earthwork, and surveying fundamentals
- Roofing systems and weatherproofing details
Domain 4: Finish Trades (20%)
Covers interior and exterior finish work that closes out a project.
- Drywall, flooring, cabinetry, and trim
- Exterior finishes and coordination sequencing
Domain 5: Safety (15%)
Covers job site safety standards and regulatory references.
- Cal/OSHA Title 8 requirements
- Fall protection, excavation, and site hazard awareness
Key Takeaway
Spend roughly a third of your review time on Core Trades alone - it outweighs Safety and Planning and Estimating combined.
Exam Format and Delivery
Both required exams - Law and Business, and Class B General Building - are proctored, computer-based, multiple-choice tests with four answer choices and a single best answer per question. The trade exam is closed book but provides a calculator for math-based items, and there is no penalty for guessing, so every question should be answered even under time pressure. It is widely reported at 115 questions across 210 minutes.
Trade exams are only offered at PSI testing centers in California and in Wilsonville, Oregon. The Law and Business exam, by contrast, can be taken out of state, which matters if you're relocating mid-application. Spanish-language versions exist for Law and Business, the B General Building trade exam, and eight other classification exams. If you're unsure how these format details translate into real difficulty, the How Hard Is the GC License Exam? guide walks through what makes this test challenging beyond raw content volume.
The current study guide governs any exam scheduled on or after January 1, 2025, and references the 2025 California Building, Residential, Electrical, Mechanical, Plumbing, Energy, Fire, and Green Building Standards Codes, plus Cal/OSHA Title 8. Studying from outdated code references is one of the most avoidable ways to lose points.
Fees, Applications, and Timelines
Money and deadlines trip up more candidates than content does. Here's the mechanical checklist:
- The Application for Original Contractor License fee is $450 and non-refundable. First-sitting exam fees are bundled into it - you don't pay separately to sit for your first attempt.
- The initial license fee is $200 for sole owners and $350 for corporations, partnerships, joint ventures, and LLCs.
- Rescheduling or retaking either exam costs $100 each time.
- If you fail an exam, you must wait 21 days before you can reschedule.
- Your application stays valid for 18 months from the date it's accepted - plan your study timeline around that window, not around an arbitrary personal deadline.
- Once licensed, renewal happens every two years.
For a full walkthrough of how these numbers stack up against total out-of-pocket cost, see the GC License Certification Cost 2026 breakdown. If you're still weighing exam calendar logistics, testing windows and scheduling nuances are covered in the GC License Exam Dates 2026 guide.
Eligibility Checklist
Before you can even sit for the trade exam, CSLB requires:
- At least 4 years of journeyman-level experience within the last 10 years (a qualifying degree can substitute for up to 3 of those years)
- Minimum age of 18
- A $25,000 contractor license surety bond on file
- Clearing Live Scan fingerprinting for state and federal background checks
Only the C-61 Limited Specialty classification skips the trade exam entirely - every other classification, including Class B, requires both the Law and Business exam and its trade exam. A more granular eligibility discussion, including edge cases around experience documentation, lives in the GC License Requirements 2026 article.
Who This License Opens Doors With
A Class B General Building license from CSLB is the credential that lets you legally contract, bid, and pull permits for general building projects in California. It's the baseline qualification residential and light commercial builders, remodeling firms, and construction management outfits look for when hiring a lead contractor or bringing on a licensed partner. Because Core Trades makes up 30% of the exam content, employers and clients alike treat a passing score as evidence you can coordinate plumbing, electrical, HVAC, and structural work - not just frame a wall. If you're evaluating whether the investment of time and fees pays off relative to your career goals, the Is the GC License Certification Worth It? analysis and the GC License Salary Guide 2026 are worth reading before you commit to an application cycle.
Key Takeaway
The license itself is a legal requirement to contract in California above certain project thresholds - it's not optional credentialing, it's the gate.
Final-Week Review Cadence
You don't need a twelve-week plan for a cheat sheet - you need a tight, domain-weighted final push. Use short, focused review blocks (25-30 minutes each) and rotate through domains in proportion to their exam weight, not evenly.
Core Trades (30%)
- Drill plumbing, electrical, HVAC, and roofing scenario questions
- Review concrete, earthwork, and surveying basics
Framing and Structural Components (20%) + Finish Trades (20%)
- Alternate between structural systems and finish-trade sequencing
- Practice reading plan sets tied to each
Planning and Estimating (15%) + Safety (15%)
- Run cost takeoff practice problems with a calculator
- Review Cal/OSHA Title 8 job site requirements
Full mixed review
- Take a full-length timed practice set at the practice test site
- Flag missed items by domain and re-review only those
This isn't generic spaced repetition for its own sake - it's allocated directly by the official domain weights, so your last days of review mirror the actual exam blueprint rather than a one-size-fits-all schedule.
Exam-Day Reminders
- Confirm your PSI center location in advance - trade exams are only offered in California and in Wilsonville, Oregon.
- Bring valid ID; Live Scan and background clearance should already be on file well before your scheduled date.
- Answer every question - there's no penalty for guessing, so leaving items blank only costs you points.
- Use the provided calculator deliberately on Planning and Estimating math items; don't eyeball takeoff calculations.
- If you don't pass, you must wait 21 days before rescheduling, and each reschedule/retake costs $100 - plan your prep so you're not paying that fee twice.
For broader context on how this exam compares in difficulty to what candidates expect going in, revisit the difficulty guide, and if you want to see how outcomes trend, the GC License Pass Rate 2026 article lays out what the available data shows. When you're ready to test your recall against exam-style questions, practice questions modeled on the real domain weights are the fastest way to find gaps before test day.
FAQ
Yes. Every fact here - domain weights, fees, question counts - comes from the official content specifications for the California Class B General Building Contractor trade exam administered by PSI for CSLB.
It's widely reported at 115 questions with a 210-minute time limit, closed book, with a calculator provided for math items.
Core Trades, at 30% of the exam. It covers plumbing, electrical, HVAC, concrete, earthwork and surveying, insulation, acoustical and weatherproofing, and roofing - more weight than any other single domain.
You must wait 21 days before rescheduling, and each reschedule or retake costs $100.
No. Only the C-61 Limited Specialty classification waives the trade exam requirement; every other classification, including Class B, requires both the Law and Business exam and a classification-specific trade exam.