- What TX-RW Actually Stands For
- Who Issues the TX-RW and Who Administers the Exam
- Exam Format: Questions, Timing, and Scoring
- What the Exam Actually Tests
- The Open-Book NEC Rules You Must Know
- Who Can Sit for the TX-RW
- Fees, Renewal, and the License Timeline
- What a TX-RW License Actually Lets You Do
- How to Approach Studying by Domain Weight
- Frequently Asked Questions
- TX-RW means Texas Residential Wireman Electrician License Exam, regulated by TDLR and delivered by PSI.
- The exam has 80 scored questions plus 5 unscored pilot items, totaling 85 questions in 4 hours 20 minutes.
- Passing requires 70%, and the exam is open-book using a properly tabbed NEC only.
- Electrical Services, Service Equipment, and Separately Derived Systems carries the most weight at 16 questions.
What TX-RW Actually Stands For
TX-RW stands for the Texas Residential Wireman Electrician License Exam - the state-administered credentialing test that qualifies an individual to legally perform electrical work on residential and light multifamily structures in Texas. This is not a national certification, a manufacturer credential, or a voluntary industry badge. It is a regulatory licensing exam tied directly to the Texas Department of Licensing and Regulation (TDLR), and passing it is a legal prerequisite to holding the Residential Wireman license in the state.
If you've seen "TX-RW" used elsewhere to describe something unrelated to Texas electrical licensing, that is a different credential entirely - this article, and this site, is built exclusively around the Texas Residential Wireman path. For a deeper breakdown of the term itself, see TX-RW Meaning and What Does TX-RW Stand For?
Who Issues the TX-RW and Who Administers the Exam
The Texas Department of Licensing and Regulation (TDLR) is the state agency responsible for the Residential Wireman license itself - setting eligibility rules, application requirements, and renewal terms. TDLR does not proctor the exam directly; that job belongs to PSI Services LLC, the third-party testing vendor that operates the computer-based testing centers where candidates actually sit for the exam.
This two-party structure matters practically: your application and eligibility paperwork goes through TDLR, but your exam scheduling, testing rules, and day-of logistics come from PSI's candidate bulletin. Understanding this split helps you know where to look when questions come up about eligibility versus test-day procedure. If you're still mapping out the full application chain, TX-RW Requirements 2026: Eligibility, Prerequisites & How to Qualify walks through it step by step.
Exam Format: Questions, Timing, and Scoring
The TX-RW exam is a computer-based, multiple-choice test delivered through PSI. Here's exactly what you're walking into:
- 80 scored questions, given 240 minutes (4 hours) to complete.
- 5 additional unscored pilot questions, given an extra 20 minutes.
- Total: 85 questions in 4 hours 20 minutes.
- Passing score: 70% based on the 80 scored questions.
- Available in English and Spanish.
The unscored questions are indistinguishable from scored ones during the test, so there's no strategic value in trying to guess which five don't count - treat every question with equal seriousness. For the precise scoring mechanics and what 70% actually translates to in raw correct answers, see TX-RW Passing Score 2026: Exactly What You Need to Pass.
Key Takeaway
Budget your test-day time as roughly 3 minutes per question across the full 4 hours 20 minutes - but expect calculation-heavy questions in some domains to eat more time than definition-based ones.
What the Exam Actually Tests
The TX-RW exam draws its 80 scored questions from ten defined content domains, each with an official item count. This is not evenly distributed - some domains carry far more weight than others, which should directly shape how you allocate study time.
| Domain | Scored Questions |
|---|---|
| 1. Definitions, Calculations, Theory, and Plans | 8 |
| 2. Electrical Services, Service Equipment, and Separately Derived Systems | 16 |
| 3. Electrical Feeders | 7 |
| 4. Branch Circuit Calculations and Conductors | 14 |
| 5. Electrical Wiring Methods and Electrical Materials | 10 |
| 6. Electrical Equipment and Devices | 12 |
| 7. Motors and Generators | 2 |
| 8. Electrical Control Devices and Disconnecting Means | 2 |
| 9. Special Occupancies, Equipment, and Conditions | 7 |
| 10. Renewable Energy Technologies | 2 |
Notice that three domains alone account for nearly half the exam: Electrical Services, Service Equipment, and Separately Derived Systems (16 questions), Branch Circuit Calculations and Conductors (14 questions), and Electrical Equipment and Devices (12 questions). Meanwhile, Motors and Generators, Electrical Control Devices and Disconnecting Means, and Renewable Energy Technologies each contribute only 2 questions - important to know, but not where you should spend disproportionate prep time.
Electrical Services, Service Equipment, and Separately Derived Systems
As the single largest domain on the exam, this area covers service entrance conductors, service equipment ratings, grounding electrode systems, and separately derived system requirements - all core to how a dwelling's electrical system is fed and protected.
- Service sizing and equipment clearance requirements
- Grounding electrode conductor sizing
- Bonding requirements for separately derived systems
Branch Circuit Calculations and Conductors
The second-heaviest domain, this tests your ability to size conductors, calculate branch circuit loads, and apply ampacity and derating rules correctly under standard methods.
- Conductor ampacity tables and correction factors
- Branch circuit load calculations for dwelling units
- Voltage drop considerations
For a full walkthrough of every domain with subtopic detail, TX-RW Exam Domains 2026: Complete Guide to All 10 Content Areas is the most thorough resource on this. And if you want a sense of how these domain weights translate into overall exam difficulty, read How Hard Is the TX-RW Exam? Complete Difficulty Guide 2026.
The Open-Book NEC Rules You Must Know
One of the most distinctive features of the TX-RW exam is that it's open-book - but with strict conditions that trip up unprepared candidates.
- You may bring a softbound NEC with notes, highlighting, or underlining you completed before the exam.
- Permanent index tabs are allowed only if manufactured or provided by the NEC publisher.
- Homemade tabs, third-party tabs, movable tabs, added sheets, the NEC Handbook, and loose-leaf, spiral-bound, or ring-bound books are all prohibited.
- You cannot mark or write in the book during the actual test - an electronic notepad is provided for scratch work instead.
Also worth internalizing: unless a question explicitly says otherwise, you should assume copper conductors and standard calculation methods. Code exceptions and optional calculation methods only apply when the question specifically directs you to use them - don't overthink a straightforward question by assuming an exception applies.
Who Can Sit for the TX-RW
Before you can even schedule the exam, TDLR requires proof of qualifying experience or training. There are two accepted paths:
- 4,000 documented on-the-job hours supervised by a Texas-licensed Master Electrician or Residential Wireman, or
- Completion of a TDLR-approved career and technology education (CTE) program.
If you're going the supervised-hours route, you need separate signed experience verification from each supervisor you worked under - not a single combined letter. TDLR must approve your application before you're permitted to schedule with PSI, and once approved, you have one year to complete all licensing requirements, including passing the exam. If you fail an attempt, you can retake it as many times as needed within that eligibility window.
For the complete eligibility checklist including documentation specifics, see TX-RW Requirements 2026: Eligibility, Prerequisites & How to Qualify.
Fees, Renewal, and the License Timeline
Budgeting for the TX-RW involves more than just the exam fee itself:
- Examination fee: $64 per attempt (paid each time you sit, including retakes).
- Initial license application fee: $20, separate from the exam fee.
- Annual license renewal: $20, plus 4 TDLR-approved continuing education hours covering NEC updates, Texas electrician law and rules, and NFPA 70E safety.
These fees are modest compared to many trade licenses, but repeated exam attempts add up quickly at $64 each - which is exactly why targeted domain-weighted preparation matters more than generic cramming. A full cost breakdown, including how retake fees compare to first-attempt costs, is available in TX-RW Certification Cost 2026: Complete Pricing Breakdown.
Key Takeaway
Every failed attempt costs another $64 exam fee - treating your first attempt as the real attempt, not a practice run, is the most cost-effective strategy.
What a TX-RW License Actually Lets You Do
The Residential Wireman license scope is specific: it covers electrical work on single-family and multifamily dwellings not exceeding four stories. It does not authorize commercial, industrial, or high-rise residential work - that requires a Journeyman or Master Electrician license instead.
In practice, this means TX-RW license holders are typically hired by residential electrical contractors, homebuilders, remodeling companies, and property management firms that maintain multifamily housing up to four stories. It's a common entry point into a licensed electrical career in Texas, often used by electricians who plan to later pursue a Journeyman license for broader scope.
If you're weighing whether pursuing this license fits your career goals, TX-RW Salary Guide 2026: Complete Earnings Analysis and Is the TX-RW Certification Worth It? Complete ROI Analysis 2026 both dig into the practical value of holding this license, and TX-RW Jobs covers where license holders typically find work.
How to Approach Studying by Domain Weight
Because domain weight is so uneven - 16 questions on one domain versus 2 on three others - your prep schedule should mirror that imbalance rather than treat all ten domains equally.
Heaviest domains first
- Electrical Services, Service Equipment, and Separately Derived Systems (16 questions)
- Branch Circuit Calculations and Conductors (14 questions)
Mid-weight domains
- Electrical Equipment and Devices (12 questions)
- Electrical Wiring Methods and Electrical Materials (10 questions)
Remaining domains and NEC tab practice
- Definitions, Calculations, Theory, and Plans; Feeders; Special Occupancies
- Motors/Generators, Control Devices, Renewable Energy (lower weight, don't skip entirely)
- Finalize NEC tabbing and timed practice runs
This kind of domain-first scheduling only works if you know the exact question counts going in - which is why treating the domain table above as your prep roadmap, rather than generic study advice, makes the difference. For a fully built-out week-by-week plan, see TX-RW Study Guide 2026: How to Pass on Your First Attempt, and once you're ready to test your recall under timed conditions, run through practice questions on the main practice test platform.
One more scheduling detail worth knowing before you register: the PSI bulletin updated July 9, 2026 shifts examination references to the NEC 2026 edition, effective September 1, 2026. If your test date falls near that transition, confirm which code edition applies to your scheduled exam before you finalize your NEC tabbing. Full scheduling windows and deadlines are covered in TX-RW Exam Dates 2026: Testing Windows, Deadlines & Scheduling, and a condensed reference of these facts is available in TX-RW Cheat Sheet 2026: One-Page Review of Must-Know Facts.
If you're just starting to research this license and want broader context beyond this single question, What Is TX-RW? and TX-RW Certification both provide fuller overviews, while TX-RW Training covers preparation program options and practice testing resources can help you gauge readiness before you commit to a PSI test date.
Frequently Asked Questions
TX-RW stands for Texas Residential Wireman Electrician License Exam, the TDLR-regulated licensing test for residential electrical work in Texas, administered through PSI Services LLC testing centers.
Yes. Candidates may bring a softbound NEC with pre-completed notes and highlighting, along with permanent publisher-manufactured index tabs. Homemade tabs, the NEC Handbook, and spiral-bound or loose-leaf books are prohibited, and no marking is allowed during the test itself.
There are 80 scored questions with 240 minutes, plus 5 unscored questions with an additional 20 minutes, for a total of 85 questions in 4 hours 20 minutes. A 70% score is required to pass.
You need either 4,000 documented on-the-job hours supervised by a Texas-licensed Master Electrician or Residential Wireman, with separate signed verification from each supervisor, or completion of a TDLR-approved career and technology education program.
Electrical Services, Service Equipment, and Separately Derived Systems is the largest domain with 16 scored questions, followed by Branch Circuit Calculations and Conductors at 14 and Electrical Equipment and Devices at 12.