- TX-MP refers to the Texas Master Plumber License Exam administered through TSBPE and delivered by Pearson VUE.
- The current Pearson handbook lists 308 items across 360 minutes, with an optional 30-minute clock-stopped break.
- Passing requires a 70% score, and personal books/notes are prohibited during testing.
- Eligibility generally requires two years as a qualifying journeyman, or one year with an approved apprenticeship.
What Is TX-MP?
TX-MP is the site shorthand used across this domain for the Texas Master Plumber License Exam - the state licensing exam administered under the authority of the Texas State Board of Plumbing Examiners (TSBPE). Passing this exam, combined with meeting the Board's eligibility and application requirements, leads to the official credential: Master Plumber. TX-MP is not a separate certification body or a national credential - it is our way of referring to the Texas-specific licensing pathway that plumbers in Texas must complete to legally hold the Master Plumber license.
If you're comparing this to other things you've seen labeled "TX-MP" online, be careful. This site, and this article, deal exclusively with the Texas plumbing license exam and the rules published by TSBPE and Pearson VUE. For a broader breakdown of terminology, see TX-MP Meaning and What Does TX-MP Stand For?
Who Administers the Exam
Two organizations matter here. The Texas State Board of Plumbing Examiners (TSBPE) sets eligibility rules, approves applications, requires fingerprinting, and issues the actual Master Plumber license. Pearson VUE is the testing vendor - it operates the authorized test centers, publishes the current examination handbook, and delivers the computer-based test itself.
This split matters practically: your application and eligibility documentation go through TSBPE, while your test scheduling, test-day rules, and score reporting go through Pearson VUE. Confusing the two is a common source of delays for first-time applicants. For a plain-language walkthrough of who does what, see TX-MP Certification.
Exam Format and Structure
The August 2025 Pearson handbook describes the current exam as 308 items delivered over 360 minutes, with an optional additional 30-minute break that stops the clock. That's a long, dense exam - plan your test day around sustained focus, not a quick sit-down.
- Computer-based testing at authorized Pearson VUE centers
- Passing score: 70%
- Personal books and notes are prohibited
- Program-supplied references and calculation resources are provided for use during the exam
Because the test leans on provided references rather than memorized tables for some sizing tasks, your prep should emphasize knowing how to use those references quickly rather than trying to memorize every chart cold. For a deeper breakdown of scoring mechanics, read TX-MP Passing Score 2026: Exactly What You Need to Pass, and for scheduling logistics see TX-MP Exam Dates 2026: Testing Windows, Deadlines & Scheduling.
Key Takeaway
Budget your test-day time in blocks: at 308 items over 360 minutes, you have a little over a minute per item on average - leave the calculation-heavy sizing and design items room to breathe.
The 12 TX-MP Domains
The exam content is organized around 12 domain areas. These aren't arbitrary - they map to the actual scope of work a Master Plumber is legally responsible for in Texas, from code compliance to gas piping to full system design.
Domain 1: Plumbing Codes
General plumbing code knowledge forming the baseline for compliant installations.
- Core code application across common installation scenarios
Domain 2: Plumbing Codes - Water Heater Installation
Code requirements specific to water heater setup, venting, and safety devices.
- Installation clearances and code-driven safety requirements
Domain 3: OSHA Federal Regulations
Federal occupational safety and health rules relevant to plumbing work sites.
- Jobsite safety obligations tied to federal regulation
Domain 4: Texas Accessibility Standards (TAS)
How accessibility standards apply specifically to plumbing fixture placement and clearances.
- Fixture installation requirements under TAS
Domain 5: Liquefied Petroleum Gas Piping
Installation practices and code requirements specific to LP gas systems.
- LP gas piping installation rules
Domain 6: Plumbing Related Mathematics
The math skills applied throughout sizing and design tasks on the exam.
- Calculations tied to real installation and sizing problems
Domain 7: Plumbing License Law and Board Rules
TSBPE rules governing licensure, conduct, and legal responsibilities of a Master Plumber.
- Board rule knowledge tested directly on the exam
Domain 8: Fuel Gas Pipe Sizing Chart
Using sizing chart references to correctly size fuel gas piping.
- Chart-based sizing rather than pure memorization
Domain 9: Water Pipe Sizing Chart
Applying sizing chart logic to water supply piping scenarios.
- Reading and applying provided sizing references
Domain 10: Gas Fueled Appliance Vent Sizing Chart
Sizing venting for gas-fueled appliances using chart-based methods.
- Vent sizing chart application
Domain 11: Drainage System Pipe Sizing Chart
Sizing drainage piping using the applicable reference chart.
- Drainage sizing chart interpretation
Domain 12: Three-Story Sanitary Drainage and Vent Design (16 Fixtures)
A full design task: laying out a sanitary drainage and vent system across three stories for sixteen plumbing fixtures.
- Applied, multi-step system design under exam conditions
For a full walkthrough of each domain with study priorities, see TX-MP Exam Domains 2026: Complete Guide to All 12 Content Areas. Note that the Board-linked Master Plumber Examination Review Course groups these same topics into seven knowledge subjects plus four sizing-chart tasks and the three-story design problem - useful as a study outline, though its older 210-question breakdown (footer-dated February 2013, referencing 2018 IPC/IFGC/UPC) does not reflect the current 308-item exam or a current weighted blueprint. Treat that guide as a topic list, not a scoring formula.
Eligibility to Sit for the Exam
TSBPE sets eligibility before you're allowed to schedule the exam. The ordinary path requires:
- A current qualifying journeyman license held for at least two years, OR
- A current qualifying journeyman license held for one year combined with a qualifying U.S. Department of Labor-approved apprenticeship
An equivalent out-of-state Master license pathway also exists for those licensed as Masters elsewhere. All applicants go through Board approval and fingerprinting requirements as part of the process. Because eligibility rules and application forms are updated periodically, use the January 2026 examination application for current procedures rather than relying on older paperwork. Full detail is available in TX-MP Requirements 2026: Eligibility, Prerequisites & How to Qualify.
Fees and Registration
The cost structure has two separate pieces, paid to two different organizations:
| Fee | Amount | Paid To |
|---|---|---|
| Board application processing fee | $25 | TSBPE |
| Pearson VUE examination fee | $128.50 | Pearson VUE |
| Total exam-side cost | $153.50 | - |
| Initial Master license (after passing) | $75 | TSBPE |
These are the only fee figures to plan around - for a complete cost breakdown including renewal costs, see TX-MP Certification Cost 2026: Complete Pricing Breakdown.
Retakes and Waiting Periods
Pearson allows up to five attempts within one year of eligibility. If you don't pass on the first try, TSBPE enforces waiting periods before you can retest:
- 30 days after the first failed attempt
- 60 days after the second failed attempt
- 90 days after any subsequent failed attempt
These waiting periods make first-attempt preparation genuinely valuable - a failed attempt doesn't just cost the retest fee, it costs a month or more of waiting before you're even eligible to try again. If you want a realistic read on how challenging the exam is before you schedule, see How Hard Is the TX-MP Exam? Complete Difficulty Guide 2026 and TX-MP Pass Rate 2026: What the Data Shows.
After Passing: License and Renewal
Passing the exam doesn't finish the process - you still need to complete licensing with TSBPE. Once issued, the initial Master Plumber license expiration is set 6 to 18 months out from the date you pass, after which it moves to an annual renewal cycle. Renewal costs $75 and requires six approved continuing professional education (CPE) hours annually.
There's also a separate business-facing designation worth knowing about: Responsible Master Plumber. This is not the same as the Master Plumber license - it's an additional designation required for plumbing businesses, requiring an active Master license plus at least $300,000 in commercial liability insurance. If you're planning to run or be named on a plumbing business, this designation is a separate step beyond passing TX-MP.
Who Actually Needs TX-MP
The Master Plumber license (and by extension, passing TX-MP) is typically pursued by:
- Journeyman plumbers advancing their career and taking on supervisory or business-owner responsibilities
- Plumbers planning to start or be named Responsible Master Plumber for a plumbing company
- Out-of-state Master plumbers relocating to Texas who need to establish licensure through the equivalent pathway
- Apprenticeship graduates moving from journeyman-level work toward full Master status
Employers - from residential service companies to commercial mechanical contractors - often look specifically for Master-licensed plumbers when staffing supervisory roles or when a business needs a Responsible Master Plumber on record. For a look at what doors this credential opens, see TX-MP Jobs and TX-MP Salary Guide 2026: Complete Earnings Analysis. If you're still weighing whether it's worth pursuing given the time and fees involved, Is the TX-MP Certification Worth It? Complete ROI Analysis 2026 walks through the tradeoffs.
A Focused Way to Prepare
Given the domain structure, a sensible study sequence front-loads the reference-heavy sizing domains early (Domains 8-11) since those skills carry directly into the Domain 12 design task, then layers in code and law domains (1, 2, 4, 5, 7) alongside math (Domain 6) and safety (Domain 3).
Sizing Chart Fluency
- Practice reading and applying the Fuel Gas, Water, Vent, and Drainage sizing charts (Domains 8-11)
Codes and Law
- Work through Plumbing Codes, water heater-specific code items, TAS fixture rules, LP gas piping, and License Law/Board Rules (Domains 1, 2, 4, 5, 7)
Math and Safety
- Drill plumbing-related math problems and review OSHA federal regulation basics (Domains 6 and 3)
Full System Design
- Practice the three-story, 16-fixture sanitary drainage and vent design task end-to-end (Domain 12)
Timed practice matters more here than for most exams, given the 360-minute format. Build in full-length practice sessions using our practice test platform so pacing across all 308 items feels familiar before test day. A structured week-by-week plan with more detail is in TX-MP Study Guide 2026: How to Pass on Your First Attempt, and a condensed reference for last-minute review is available in TX-MP Cheat Sheet 2026: One-Page Review of Must-Know Facts.
Frequently Asked Questions
No. TX-MP is this site's shorthand for the Texas Master Plumber License Exam. Passing it, along with meeting TSBPE's application and eligibility requirements, results in the official Master Plumber license.
The August 2025 Pearson handbook lists 308 items delivered over 360 minutes, with an optional additional 30-minute clock-stopped break.
A 70% passing score is required, based on the current Pearson VUE handbook.
No. Personal books and notes are prohibited. Pearson provides program-supplied references and calculation resources for use during the test.
You can retest, but TSBPE enforces waiting periods: 30 days after a first failure, 60 days after a second, and 90 days after any subsequent failure, within a one-year eligibility window allowing up to five attempts.