ICC T18 Residential Electrician Exam (2020 NEC) Practice Exam
Free Practice Exam
Test your knowledge with 10 questions from our pool of 20 free questions.
- 10 questions per attempt
- 30 minute time limit
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Full Practice Exam
Complete exam simulation matching the real Pearson VUE test format.
- 60 questions (same as real exam)
- 180 minute time limit
- 7 topic areas covered
- 254 questions in pool
- Detailed explanations
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ICC T18 Residential Electrician (2020 NEC) Practice Exam Guide
What's on the exam
Questions per topic, out of 60This practice exam is built around the official content outline for the ICC T18 Residential Electrician (2020 NEC) exam: General Knowledge, Services and Service Equipment, Feeders, Branch Circuits and Conductors, Wiring Methods and Materials, Equipment and Devices, Special Occupancies, Equipment, and Conditions.
There are two ways to practice. The free practice exam gives you 10 questions per attempt, and you can take it as many times as you like. The full practice exam gives you 60 questions on a 3 hours clock, with a new draw from our question bank each time.
General Knowledge 7 items
Our study plan for this topic: Electrical Theory and General Electrical Load Calculations; Code Definitions and Terms; NEC Purpose, Scope, and Code Arrangement (Article 90); General Requirements for Electrical Installations (Article 110); Working Spaces and Clearances Around Electrical Equipment; Conductor Properties, Ratings, and Connections; Grounded Conductor Identification and Neutral Load Calculations; Ohm's Law, Series, Parallel, and Combination Circuit Analysis.
Services and Service Equipment 13 items
Our study plan for this topic: Service Load Calculations; Service Equipment & Service Conductors; System Grounding and Bonding; Service Disconnecting Means Requirements; Service Overcurrent Protection; Grounding Electrode System and Electrode Types; Grounding Electrode Conductor Sizing and Installation; Equipment Grounding Conductor Types and Sizing.
Feeders 8 items
Our study plan for this topic: Load Calculations; Equipment Grounding; Feeder conductor ampacity and minimum size requirements (Article 215); Overcurrent protection for feeders; Feeder neutral load calculations (Section 220.61); Optional feeder load calculations for dwelling units (Section 220.82); Demand factors for cooking appliances, clothes dryers, and kitchen equipment; Outside feeder clearances, disconnecting means, and wiring methods (Article 225).
Branch Circuits and Conductors 15 items
Our study plan for this topic: Branch Circuit Calculations; Required Outlets & GFCI/AFCI Protection; Overcurrent Protection; Equipment Grounding; Conductors; Conductor Identification (Grounded, Ungrounded, and EGC Color Coding); Ampacity Correction and Adjustment Factors (Temperature and Bundling); Voltage Drop Calculations for Branch Circuits.
Wiring Methods and Materials 8 items
Our study plan for this topic: Raceway Installations; Boxes and Enclosures; Flexible Cords and Cables; Cable wiring methods (NM, MC, SE, USE, UF) — uses permitted and not permitted; Conduit fill calculations and conductor count tables (Chapter 9 Table 1 and Annex C); Underground installation requirements and minimum cover depths (Table 300.5); Protection of cables and raceways from physical damage (NEC 300.4); Conduit bending — 90° stubs, offsets, saddle bends, and back-to-back bends.
Equipment and Devices 5 items
Our study plan for this topic: Luminaires; Receptacles, Switches and Other Devices; Appliances and Other Equipment; Luminaire installation in specific locations (wet, damp, closets, bathtub/shower areas); Recessed luminaire clearances and thermal protection (Type IC vs. non-Type IC); Lighting track installation requirements and prohibited locations; Low-voltage lighting system components, listing, and secondary circuit requirements; Switch ratings, types, and load control limitations (AC snap, dimmer, electronic control).
Special Occupancies, Equipment, and Conditions 4 items
Our study plan for this topic: Swimming Pools and Similar Installations; Low Voltage Circuits, Alarm & Similar Systems; GFCI Requirements for Pools, Spas, and Hot Tubs; Equipotential Bonding for Pool Structures and Equipment; Underwater Luminaires and Junction Box Requirements; Receptacle and Lighting Clearance Distances from Water; Fire Alarm Circuit Power Sources and Wiring Methods (NPLFA and PLFA); Class 1, Class 2, and Class 3 Circuit Classifications and Power Source Requirements.
Sample 1 — Branch Circuits and Conductors
Question: When using the next higher standard overcurrent device rating above the ampacity of conductors being protected, what is the maximum rating of that overcurrent device for this provision to apply?
- A. 400 amperes
- B. 600 amperes
- C. 800 amperes
- D. 1000 amperes
Correct Answer: C
Per NEC 240.4(B), the next higher standard overcurrent device rating is permitted provided the selected rating does not exceed 800 amperes, among other conditions.
Reference: NEC 2020 Section 240.4(B)
Sample 2 — Services and Service Equipment
Question: For bonding of circuits operating at over 250 volts to ground, the electrical continuity of metal raceways and cables with metal sheaths shall be ensured by one or more of the methods specified for services, except for bonding to the ______.
- A. Equipment grounding conductor
- B. Grounded service conductor
- C. Grounding electrode
- D. Supply-side bonding jumper
Correct Answer: B
Per NEC 250.97, for circuits of over 250 volts to ground, the electrical continuity of metal raceways and cables with metal sheaths shall be ensured by one or more of the methods specified for services in 250.92(B), except for (B)(1) — which is the method of bonding equipment to the grounded service conductor. This exception exists because the grounded service conductor bonding method is specific to service equipment only.
Reference: NEC 2020 Section 250.97
Sample 3 — Feeders
Question: A 400 A service uses 600 kcmil copper service conductors. What is the minimum size of a copper grounding electrode conductor that runs only to a concrete-encased electrode?
- A. 2 AWG
- B. 4 AWG
- C. 3/0 AWG
- D. 1/0 AWG
Correct Answer: B
Table 250.66 would require a 1/0 AWG copper grounding electrode conductor for 600 kcmil copper service conductors, but 250.66(B) says a grounding electrode conductor (or bonding jumper) that runs only to a concrete-encased electrode is not required to be larger than 4 AWG copper. So the minimum size required here is 4 AWG copper.
Reference: NEC 2020 Section 250.66(B), Table 250.66
Your first score is just a starting point. After every attempt, the results page shows how you did on each outline topic, so you can see what to work on next. Compare your score with the real exam's passing score, 70% correct, and keep at it until you pass consistently.
- Start with the questions you know. Go through the whole exam once and bookmark anything you're unsure about. Our practice exams let you bookmark and come back.
- Circle back to your bookmarks on the second pass.
- Keep an eye on your pace. The real exam works out to about 3 minutes per question.
- Turn every miss into a lesson. After each attempt, look up each missed question's reference in your book and read the section.
| Questions | 60 questions |
| Time limit | 3 hours |
| Passing score | 70% correct |
| Books in the exam room | Open book |
| Exam fee | $120 |
- Results for examinations taken electronically are available immediately after the examination is completed.
- You must wait 10 days before retaking a failed exam.
Source: National Contractor/Trades Examination Information Bulletin, PUBLISHED June 30, 2026; ICC Exam Catalog, checked September 27, 2026. Check the bulletin before test day: fees and rules can change.