- AZ-EC is the Arizona C-11 (CR-11) Electrical Commercial trade exam, administered by PSI for the Arizona Registrar of Contractors.
- The trade exam has 110 questions in 240 minutes, and you need 70% correct to pass.
- Trade exam fee is $66; the separate Statutes and Rules Exam is $61 through the ROC.
- Service Feeders and Branch Circuits, Grounding and Bonding, and Special Occupancies and Equipment tie as the largest domains at 13 items each.
What Is AZ-EC Certification?
AZ-EC refers specifically to the Arizona C-11 (CR-11) Electrical (Commercial) trade examination, one of the licensing exams administered by PSI Services LLC on behalf of the Arizona Registrar of Contractors (ROC). This is a state-specific commercial electrical outline - not the R-11 residential exam and not the NASCLA commercial electrical exam that some contractors choose as an alternative path in other states. If you're new to this credential and want a plain-language explanation before diving into specifics, our overview at What Is AZ-EC? and companion piece AZ-EC Meaning cover the basics of what the acronym stands for and why the ROC requires it.
The current bulletin governing this exam is dated February 18, 2026, while the commercial trade outline itself was last revised June 8, 2023. That gap matters: the underlying content blueprint has been stable for a while, even as administrative details in the bulletin get periodic updates. Candidates preparing today should reference the latest bulletin for procedural details but can treat the domain structure and weighting as a mature, well-tested outline.
Exam Format and Blueprint
The C-11 commercial trade exam is delivered as computer-based multiple-choice testing, available either at a physical PSI test center or through remote proctoring. Candidates get 110 scored questions and 240 minutes to complete them. PSI may also insert 5 to 10 unscored experimental questions into the exam without adding extra time - meaning your actual working time per question is effectively a bit tighter than 240/110 suggests, since some of those minutes go toward items that don't count toward your score but you can't identify which ones they are.
You need 70% correct to pass. For a full breakdown of exactly how that threshold is calculated against the 110-item blueprint, see AZ-EC Passing Score 2026: Exactly What You Need to Pass.
If you're testing remotely, know the constraints going in: remote proctoring prohibits breaks and prohibits scratch paper. That's a meaningful difference from in-center testing, where policies around approved calculators and reference materials still apply but the break/scratch-paper restrictions of remote sessions don't. Choose your testing modality deliberately rather than defaulting to whichever seems more convenient to schedule.
Key Takeaway
If you plan to test remotely, practice working problems mentally or directly on-screen beforehand - you won't have scratch paper as a crutch during the real exam.
The 15 Domains, Ranked by Weight
PSI publishes the exact item allocation for the C-11 commercial outline, and it's worth memorizing the general shape of this distribution before you study anything else. The 15 domains and their item counts, in domain order, are: 5, 13, 13, 12, 10, 13, 2, 5, 5, 3, 1, 5, 5, 8, 10 - totaling 110 items.
Three domains tie for the largest share at 13 items each: Service Feeders and Branch Circuits, Grounding and Bonding, and Special Occupancies and Equipment. Together these three domains account for 39 of the 110 questions - roughly a third of the entire exam. Any study plan that doesn't give these three areas outsized attention is misallocating effort.
Service Feeders and Branch Circuits (13 items)
Candidates must understand feeder and branch circuit sizing, load calculations, conductor ampacity adjustments, and the commercial application of these rules under the 2017 NEC.
- Feeder conductor sizing and derating
- Branch circuit load calculations for commercial occupancies
- Voltage drop considerations on longer runs
Grounding and Bonding (13 items)
This domain tests grounding electrode systems, equipment grounding conductors, bonding of service equipment, and separately derived systems as they apply to commercial installations.
- Grounding electrode conductor sizing
- Bonding jumpers and equipment grounding paths
- Grounding requirements for separately derived systems
Special Occupancies and Equipment (13 items)
Covers NEC provisions for hazardous locations, health care facilities, and other special-purpose commercial spaces along with associated equipment requirements.
- Classified/hazardous location wiring methods
- Special equipment listing and installation rules
- Occupancy-specific code exceptions
On the smaller end, Illuminated Signs carries just 1 item and Devices carries 2 items - meaning you should not overinvest study hours there relative to the big three. Rounding out the mid-weight domains: Conductors and Cables (12), Photovoltaics and Lighting (10 each), Overcurrent Protection (8), and General Electrical Knowledge, Motors, Low Voltage, Fire Detection and Alarm Systems, and Safety at 5 each, with Raceways and Boxes at 5 and Lighting-adjacent items rounding out the rest.
For a full walkthrough of every one of the 15 domains - including specific NEC articles and NFPA 72 sections tied to each - read AZ-EC Exam Domains 2026: Complete Guide to All 15 Content Areas. It's the most detailed domain-by-domain resource we publish and pairs well with this overview.
Who Qualifies and What It Costs
To sit for the C-11 commercial trade exam as a qualifying party, you ordinarily need four years of practical or management experience in the electrical trade, with at least two of those years falling within the preceding ten years. Qualifying education or manufacturer training can offset up to two years of that requirement - so formal coursework or documented manufacturer programs can meaningfully shorten the experience timeline for some candidates. Full eligibility mechanics, including business, background, bond, and insurance requirements that apply alongside the trade exam, are detailed in AZ-EC Requirements 2026: Eligibility, Prerequisites & How to Qualify.
On cost: the trade exam fee is $66. Separately, candidates must also pass the Statutes and Rules Exam, which costs $61 through the ROC's online process. These are two distinct exams with two distinct fees - budget for both. A complete pricing breakdown, including how these fees fit into the total cost of getting licensed, is available in AZ-EC Certification Cost 2026: Complete Pricing Breakdown.
| Item | Detail |
|---|---|
| Trade Exam Fee | $66 |
| Statutes and Rules Exam Fee | $61 |
| Trade Exam Length | 110 questions, 240 minutes |
| Passing Score | 70% |
| Experience Requirement | 4 years (2 within preceding 10 years); up to 2 years credit for qualifying education/training |
Open-Book References and Materials
Unlike many trade exams, the C-11 commercial exam is open-book with respect to three specific reference documents: the 2017 National Electrical Code, NFPA 72 National Fire Alarm Code (2016), and the specified 29 CFR 1926 OSHA reference. This is a significant advantage if you use it correctly - but it also means the exam is testing your ability to navigate and apply code rather than pure memorization.
Your approved books can be pre-highlighted, underlined, annotated, and permanently tabbed before you arrive. This preparation work is not optional busywork - it's the single highest-leverage thing you can do before test day, because rapid navigation to the right NEC article under time pressure is often the difference between finishing all 110 questions and running out of time. What's prohibited: adding loose papers into your books, and writing in the books during the actual exam session. Tab and annotate beforehand; don't plan to modify your references mid-test.
You'll also need a basic non-scientific, non-programmable calculator that meets PSI's device rules. Don't assume your everyday scientific calculator qualifies - check the bulletin's calculator policy before test day, especially if you're used to a more advanced model from other coursework.
Key Takeaway
Tab your 2017 NEC, NFPA 72 (2016), and OSHA 29 CFR 1926 reference by domain topic before test day - annotation during the exam itself is not allowed.
Retakes, Deadlines and Licensing Timeline
If you don't pass on your first attempt, the standard waiting period before retaking is 30 days. If you fail a third time (and on any subsequent attempt after that), the waiting period extends to 90 days. This escalating structure rewards focused preparation between attempts rather than repeated quick retries - use the wait productively by revisiting the domains where you missed the most questions, particularly the three 13-item domains if they weren't your strong suit.
Once you pass, don't sit on it: a qualifying exam pass must be used toward a license application within two years, or it expires and you'd need to retest. After licensing, contractor licenses renew on a two-year cycle, requiring the renewal filing, applicable fee, and a maintained bond. For a broader view of how testing windows and administrative deadlines fit together across the whole process, see AZ-EC Exam Dates 2026: Testing Windows, Deadlines & Scheduling.
Building a Domain-Weighted Study Plan
Rather than studying domains in the order they're listed, allocate your calendar time proportionally to item weight. A simple, AZ-EC-specific approach:
The Big Three
- Service Feeders and Branch Circuits (13 items) - load calcs, conductor sizing
- Grounding and Bonding (13 items) - electrode systems, bonding jumpers
- Special Occupancies and Equipment (13 items) - hazardous locations, health care facilities
Mid-Weight Domains
- Conductors and Cables (12 items)
- Photovoltaics and Lighting (10 items each)
- Overcurrent Protection (8 items)
Remaining Domains and Review
- General Electrical Knowledge, Motors, Low Voltage, Fire Detection and Alarm Systems, Safety, Raceways and Boxes (5 items each)
- Devices (2 items) and Illuminated Signs (1 item) - brief review only
- Full practice run using your tabbed reference books
This weighting isn't a generic template - it's built directly from PSI's published item allocation for this specific outline. For a deeper dive into structuring your prep week-by-week, including how to interleave code-book navigation drills with practice questions, see AZ-EC Study Guide 2026: How to Pass on Your First Attempt. If you want a compact reference for last-minute review, bookmark AZ-EC Cheat Sheet 2026: One-Page Review of Must-Know Facts, and pair your studying with realistic practice questions on our practice test platform to get comfortable with the multiple-choice format before test day.
Many candidates also want a realistic sense of how challenging this specific exam is relative to their background. Our detailed breakdown at How Hard Is the AZ-EC Exam? Complete Difficulty Guide 2026 and the data-driven look in AZ-EC Pass Rate 2026: What the Data Shows can help you calibrate expectations without relying on rumors from unrelated trades or forums.
Who Hires AZ-EC Licensed Contractors
Holding a C-11 commercial electrical license through the Arizona ROC positions you to bid and perform commercial electrical work as a licensed contractor or qualifying party in Arizona - from tenant improvements and new commercial construction to special-occupancy installations covered under this exam's domains, like health care facilities and classified locations. General contractors, electrical subcontracting firms, and property developers working on commercial projects across Arizona typically need a licensed C-11 qualifying party attached to any electrical scope of work.
If you're evaluating whether pursuing this license makes financial and career sense for your situation, our analysis at Is the AZ-EC Certification Worth It? Complete ROI Analysis 2026 walks through the considerations, and AZ-EC Salary Guide 2026: Complete Earnings Analysis covers earnings context for licensed commercial electrical contractors. For those exploring the job market itself, AZ-EC Jobs rounds out where licensed contractors typically find work, and AZ-EC Training covers training pathways that can also count toward your qualifying experience credit.
Before you commit to a testing date, it's worth reviewing the fundamentals one more time - start with What Is AZ-EC Certification? and What Does AZ-EC Stand For? if you're still confirming this is the exact credential your project or employer requires, since the C-11 commercial outline is distinct from the R-11 residential path. You can also browse practice questions anytime on the main AZ-EC practice test site to see how the question style feels before locking in a test date.
Frequently Asked Questions
The exam has 110 scored questions to be completed in 240 minutes. PSI may add 5 to 10 additional unscored experimental questions without extending your time.
You need 70% correct on the 110-question trade exam to pass.
Yes, for the three approved references - the 2017 NEC, NFPA 72 (2016), and the specified 29 CFR 1926 OSHA reference. You may pre-highlight, underline, annotate, and permanently tab these books, but you cannot add loose papers or write in them during the exam.
The trade exam fee is $66. There's also a separate Statutes and Rules Exam that costs $61 through the ROC's online process.
You must wait 30 days before retesting. If you fail a third time, the waiting period extends to 90 days for that and any subsequent attempts.
A qualifying exam pass must be applied toward a license application within two years of passing, after which it expires.