Oklahoma Residential Electrical Contractor

Oklahoma Residential Electrical Contractor Exam: Complete 2026 Prep Guide

You've put in the hours on the job. Now you need to pass the Oklahoma Residential Electrical Contractor exam to make it official. This exam is 80 questions, covers the full range of residential electrical work — from NEC code to safety to special occupancies — and you need a 70% to pass. This guide breaks down exactly what's on it, what books to bring, and how to prepare. Start with our free practice exam to see where you stand right now.

Exam Overview: What to Expect on Test Day

The Oklahoma Residential Electrical Contractor exam is administered through PSI. Here are the numbers that matter:

• Questions: 80 scored items (additional unscored experimental questions may appear but do not count against you)
• Time: 210 minutes
• Passing score: 70% — that's 56 out of 80 scored questions correct
• Format: Open book; bring your own approved references

The exam is open book, which sounds like a relief — but it's not a research project. You won't have time to look up every answer. Know your material cold, use your books to confirm specifics like table values, and keep them tabbed so you can find things fast.

For the full breakdown of what's tested, check the official exam bulletin.

Topics Covered on the Oklahoma Residential Electrical Contractor Exam

The exam draws from 12 topic areas. Here's how they break down by question count:

• General Electrical Knowledge — 12 items: Ohm's Law, circuit analysis, voltage drop, electrical formulas
• Electrical Installation Requirements — 10 items: branch circuits, GFCI/AFCI, receptacle placement, lighting outlets
• Services, Feeders, and Branch Circuits — 10 items: service sizing, load calculations, disconnecting means
• Overcurrent Protection — 8 items: conductor protection, fuse types, device location rules
• Grounding and Bonding — 8 items: electrodes, conductor sizing, bonding jumpers
• Special Occupancies and Equipment — 8 items: pools, mobile homes, RVs, hazardous locations
• Raceways and Boxes — 6 items: conduit fill, box fill, support intervals
• General Knowledge — 4 items: NEC scope, code arrangement, AHJ rules
• Conductors and Cables — 4 items: insulation types, ampacity tables, NM cable
• Low Voltage, Alarms, Signaling Systems, and Communications — 4 items: fire alarm circuits, cable types
• Safety — 4 items: lockout/tagout, PPE, arc-flash, shock protection
• Lighting and Signs — 2 items: luminaire placement, recessed fixture rules, lighting track

Focus your study time where the exam puts the most weight. General Electrical Knowledge, Electrical Installation Requirements, and Services/Feeders/Branch Circuits together account for 32 of the 80 questions — that's 40% of the exam right there.

Sample Questions

Here's a look at five real-style questions from the Oklahoma Residential Electrical Contractor exam prep pool. Try them on your own first, then check our practice exam for answers and explanations.

Question 1 — Services, Feeders, and Branch Circuits (Medium)
When using the standard load calculation method for a single household electric range rated at 12 kW or less, what is the maximum demand load permitted?

A) 10 kW
B) 6 kW
C) 8 kW
D) 12 kW

Question 2 — Services, Feeders, and Branch Circuits (Easy)
A surge-protective device (SPD) installed at service equipment supplying a dwelling unit must have a nominal discharge current rating (In) of not less than:

A) 5 kA
B) 15 kA
C) 10 kA
D) 20 kA

Question 3 — Overcurrent Protection (Medium)
For a feeder tap not over 7.5 m (25 ft) long, the ampacity of the tap conductors must be not less than what fraction of the rating of the overcurrent device protecting the feeder conductors?

A) One-third
B) One-quarter
C) One-half
D) One-tenth

Question 4 — Raceways and Boxes (Medium)
You are wiring a residential addition and need to install 12 THHN 14 AWG conductors in electrical metallic tubing (EMT). What is the minimum trade size EMT permitted?

A) ½ inch
B) 1¼ inch
C) 1 inch
D) ¾ inch

Question 5 — Overcurrent Protection (Medium)
A panelboard is protected by two main circuit breakers instead of a single main breaker. Under what condition is this arrangement permitted, and what is the maximum number of overcurrent devices the panelboard may contain?

A) In any installation; limited to 48 overcurrent devices
B) Only in service equipment; limited to 30 overcurrent devices
C) Only in service equipment, with combined rating not exceeding the panelboard rating; limited to 42 overcurrent devices
D) In other than service equipment, with combined rating not exceeding the panelboard rating; limited to 42 overcurrent devices

Not sure where you landed? Take our free practice exam and find out.

What Types of Questions to Expect

Our full practice library has 411 questions across all 12 exam topics. Here's what each section actually tests:

• General Knowledge (20 practice questions): NEC scope, chapter layout, mandatory vs. permissive language, AHJ authority, and unit systems. Expect definitions and code-structure questions.
• General Electrical Knowledge (60 practice questions): Ohm's Law calculations, series/parallel circuits, voltage drop for single- and three-phase systems, and conductor identification. Heavy on math.
• Electrical Installation Requirements (50 practice questions): Branch-circuit sizing, GFCI and AFCI location requirements, receptacle spacing rules, and required lighting outlets — the day-to-day NEC rules for residential work.
• Services, Feeders, and Branch Circuits (51 practice questions): Service sizing, load calculations with demand factors, disconnecting means requirements, and voltage drop. Expect calculation-heavy questions.
• Overcurrent Protection (43 practice questions): Conductor protection rules by AWG, standard fuse and breaker ratings, feeder tap rules, device location restrictions, and fuse type identification.
• Grounding and Bonding (40 practice questions): Electrode types and installation, grounding electrode conductor sizing from Table 250.66, equipment grounding conductor sizing from Table 250.122, and bonding jumper requirements.
• Conductors and Cables (20 practice questions): Insulation type applications, ampacity tables (310.16 and 310.17), temperature correction and adjustment factors, and NM cable installation rules.
• Raceways and Boxes (32 practice questions): Conduit fill calculations by raceway type, support intervals, box fill calculations, and box sizing for outlet, pull, and junction boxes.
• Special Occupancies and Equipment (40 practice questions): Pool and spa bonding, overhead clearances, mobile home power supply requirements, RV park receptacle configurations, and hazardous location classifications.
• Low Voltage, Alarms, Signaling Systems, and Communications (24 practice questions): Fire alarm circuit types, cable listings (FPL, FPLR, FPLP), separation rules for mixed-use raceways, and communications cable type applications.
• Lighting and Signs (11 practice questions): Luminaire location rules (wet, damp, closet), recessed fixture clearances, Type IC vs. non-IC, and lighting track installation limits.
• Safety (20 practice questions): Lockout/tagout steps, PPE selection, arc-flash boundaries, shock protection distances, and GFCI program requirements.

Required Study Materials

The Oklahoma Residential Electrical Contractor exam is open book, but you must bring your own copies of the approved references. Here's what you need:

Required references:

• NEC 2023 — National Electrical Code: The primary reference for this exam. Get the standard edition — NEC Handbooks and spiral-bound copies are NOT permitted in the exam room.
• OSHA 29 CFR 1926: The construction industry safety standard. Bring the edition with the latest amendments.
• Ugly's Electrical References: Any edition is accepted. Compact, quick to flip through, and handy for common formulas and table values.

Highly recommended study tools:

• Sharpie Tank Highlighters: Fluorescent ink that stands out and resists smearing. You're allowed to highlight your references before the exam — do it. Mark the tables you'll need: 310.16, 240.6(A), 250.66, 250.122. A 12-pack gives you enough colors to code by topic.
• Redi-Tag Permanent Colored Tabs: Permanent adhesive, laser-printable, and they stay put through hundreds of page flips. Tab every major article and table you'll reference. This is the difference between finding an answer in 30 seconds and burning 3 minutes hunting.

You are allowed to highlight, underline, and index your references with permanent tabs before the exam. You may NOT write notes or formulas in the margins.

Study Tips for the Oklahoma Residential Electrical Contractor Exam

Tab and highlight before test day. Go through your NEC and mark every table and article listed in the exam topics. You should be able to find Table 310.16 in under five seconds.

Answer what's actually asked. Read each question carefully. Pick the answer that directly responds to what was asked — not the one that sounds the most technically impressive or seems like it might be true in some situation. After choosing, re-read the question and verify your answer actually addresses it.

Trust what you know. If you've studied and an answer choice is full of unfamiliar terms, that's a flag. An option you don't recognize at all is rarely correct. Distractor answers are often designed to sound plausible. Stick with what you've learned.

Every attempt is different. Each time you sit for the exam, you'll get a different set of questions in a different order — but always drawn from the same topic areas and in the same proportions. Consistent topic-by-topic studying beats memorizing specific questions.

Do the math by hand. Voltage drop, load calculations, conduit fill — practice these without looking at the answer. The exam gives you a calculator, but you still need to know the formula.

FAQs: Oklahoma Residential Electrical Contractor License

How many questions are on the Oklahoma Residential Electrical Contractor exam and how long do I have?
The exam has 80 scored questions. You get 210 minutes to complete it. A small number of additional unscored experimental questions may appear — they don't count against your score.

What is the passing score?
You need 70% — that's 56 correct out of 80 scored questions.

How much does the exam cost?
The exam fee is $92 per portion. It's non-refundable and non-transferable, whether you're taking it for the first time or retaking it.

How do I register?
First, get approved by the Oklahoma Construction Industries Board. Once approved, you'll receive an OK Con ID number. Use that to create an account and schedule your exam through PSI at the exam registration page, or call PSI at (855) 834-8750.

What if I fail?
If you fail on the first attempt, you must wait 30 days before retesting. The same 30-day waiting period applies to any additional retakes after that.

Does my exam eligibility expire?
No. Once the Oklahoma Construction Industries Board approves you, your eligibility doesn't expire.

Is the exam open book?
Yes. Bring your approved references — highlighted, tabbed, and ready. You cannot write notes in them, but highlighting and permanent tabs are allowed.

What references can I bring?
NEC 2023 (standard edition — no Handbook, no spiral-bound), OSHA 29 CFR 1926 with latest amendments, and Ugly's Electrical References (any edition). All copies must be your own.

Can I bring a calculator?
Yes — silent, battery-operated, non-printing, non-programmable, and no alphabetic keyboard. A magnifying glass is available upon request.

What ID do I need?
One valid, non-expired, signature-bearing photo ID. A state driver's license, U.S. passport, military ID, alien registration card, or Canadian government-issued ID all work. The name must match your registration exactly.

Get Started Today

The Oklahoma Residential Electrical Contractor exam is manageable when you know the material and have your references organized. Eighty questions, 210 minutes, and a 70% passing score — those are fair numbers if you put in the prep work.

Start by taking our free practice exam — 10 questions, no account needed, instant results. When you're ready to go deeper, the full practice exam matches the real exam format, pulls from a pool of 411 questions across all 12 topics, and gives you a detailed score breakdown by topic so you know exactly where to focus. Good luck — you've got this.