- What a NM2GI Actually Is
- Who Issues It and What GLI05 Means
- The Five Module Groups in Full-Route Preparation
- Q100 or Q300: Choosing the Rules Module
- Modules That Are Not Part of the Original Master Route
- Why Chart Plot Q343 Deserves Its Own Plan
- Who Hires Holders of a Master or Mate Under 200 GRT
- Your Approval to Test Is the Real Blueprint
- Sequencing Your Preparation Around the Modules
- Frequently Asked Questions
- NM2GI here means National Master 200 GL and Inland, governed by the U.S. Coast Guard National Maritime Center under scope GLI05.
- GLI05 covers Master or Mate less than 200 GRT on Great Lakes and Inland routes.
- Full-route preparation spans five module groups: Q100 or Q300, Q340, Q341, Q342 and Q343.
- Q100 and Q300 are alternatives, so they are never two simultaneous requirements.
What a NM2GI Actually Is
If you searched "what is a NM2GI," you have probably noticed that the acronym gets attached to several unrelated credentials. On this site, NM2GI means National Master 200 GL and Inland, a mariner credential pathway for people who want to serve as Master or Mate on vessels of less than 200 gross register tons (GRT) operating on the Great Lakes and inland waters of the United States. It is a maritime licensing route, not an IT, project management or healthcare certification, and nothing in this article applies to any of those.
The "200" refers to the tonnage ceiling of the vessels the credential covers. "GL" refers to Great Lakes, and "Inland" refers to inland waters. Taken together, the name describes the operating area and vessel size that the endorsement addresses. For a broader walk-through of the term itself, see our related explainers, including What Is NM2GI? and What Does NM2GI Stand For?.
Who Issues It and What GLI05 Means
The governing body is the United States Coast Guard National Maritime Center (NMC). The NMC publishes the examination modules and topic matrices for mariner endorsements, and it is the NMC that evaluates your application and determines what you must test on. The scope code for this credential is GLI05, which the NMC describes as Master or Mate less than 200 GRT.
Two things follow from that. First, the content you study is publicly documented by the issuer, so there is no mystery about what subject areas exist. Second, because the NMC assigns modules to each applicant individually, two mariners pursuing "the same" endorsement may be asked to complete different sets of modules depending on their route and prior credentials.
The Five Module Groups in Full-Route Preparation
For full-route preparation on the Great Lakes and Inland or Inland-only routes, the published structure comes down to five module groups. These are organized here as unweighted groups. No official percentage weighting, single overall question count or single overall exam duration is established for them, so treat any site that quotes such numbers as a single fact with suspicion. For a deeper breakdown, see NM2GI Exam Domains 2026: Complete Guide to All 5 Content Areas.
Domain 1: Rules of the Road: Inland and International (Q100)
The navigation rules module. For Great Lakes and Inland, this is Q100. An Inland-only applicant may use Q300 instead when the applicable COLREGS limitation is accepted.
- Steering and sailing rules and vessel right-of-way relationships
- Lights, shapes and sound signals
- The distinction between Inland and International rules, and where each applies
Domain 2: Deck General (Q340)
Core seamanship and vessel-handling knowledge that a person in charge of a small commercial vessel is expected to command.
- General deck operations and vessel familiarity
- Everyday seamanship that underpins safe operation
Domain 3: Deck Safety (Q341)
The safety-focused module, covering the practices and knowledge that protect people and the vessel.
- Onboard safety practices and emergency awareness
- Responsibilities of the licensed officer for crew and passenger safety
Domain 4: Navigation General: Great Lakes and Inland (Q342)
The navigation theory module tailored to Great Lakes and inland operations.
- Piloting concepts and navigation aids relevant to these waters
- Route-appropriate navigation knowledge for Great Lakes and Inland operators
Domain 5: Navigation Problems: Chart Plot (Q343)
The applied chart-work module. It is required in the full-exam structure and must not be omitted when planning your preparation.
- Working chart-plotting problems rather than only recalling definitions
- Accurate, methodical chart work under test conditions
| Route | Exact full-route module set | Count |
|---|---|---|
| Great Lakes and Inland | Q100, Q340, Q341, Q342, Q343 | 5 modules |
| Inland | Q100 OR Q300, Q340, Q341, Q342, Q343 | 5 modules |
The published guide reference for this scope is 2.1.2.3, printed page 27 of the NMC deck and engineering guide. That guide reflects regulations effective March 24, 2014, so it is a published reference document rather than a newly issued 2026 blueprint. Current indexed NMC matrices corroborate the module headings used here.
Q100 or Q300: Choosing the Rules Module
One of the most common misunderstandings is counting both rules modules. Q100 and Q300 are alternatives, not two extra domains. A Great Lakes and Inland route uses Q100. An Inland route may use Q300 when the applicable COLREGS limitation is accepted. You do not prepare for both as simultaneous requirements, and you should never add them together when you tally how many modules you face.
Because the rules module is the one place where your route changes the content you study, confirm with your approval to test which one applies before you invest weeks in either. Our NM2GI Requirements 2026: Eligibility, Prerequisites & How to Qualify article covers how route and eligibility interact.
Modules That Are Not Part of the Original Master Route
The NMC publishes additional modules in the same family, and candidates sometimes mistake them for extra hurdles on the original route. They are not.
- Q345 Navigation and Deck General/Safety is a separate raise-of-grade module, relevant when moving from Master under 100 to Master or Mate under 200.
- Q346 is a separate route for an OUPV moving up to Mate under 200. It is not an extra Master-original module.
Upgrade, raise-of-grade and route-extension modules are not additional full-original-exam domains. This is why the five-group structure above is a preparation framework rather than a universal count of examinations for every applicant. Someone upgrading may sit a different, smaller set than someone testing for the original credential.
Why Chart Plot Q343 Deserves Its Own Plan
Four of the five groups are largely knowledge modules. Q343 is different because it asks you to do something rather than recall something. Candidates who feel comfortable with the rules and general modules can still stumble here if they have not practiced working plotting problems by hand and checking their own work.
Treat Q343 as a skill to be trained, not a topic to be read about. Build repetition into your routine: work problems, check your method, and look for the specific step where errors creep in. The module is required in the full-exam structure, so leaving it for the last few days before your test is a risky choice. For a candid look at where candidates struggle, see How Hard Is the NM2GI Exam? Complete Difficulty Guide 2026.
Key Takeaway
Schedule chart-plot practice early and repeatedly. It is the one module where fluency comes from doing problems, so give it more calendar time than its single module slot suggests.
Who Hires Holders of a Master or Mate Under 200 GRT
A credential covering vessels under 200 GRT on the Great Lakes and inland waters points toward operators of small to mid-sized commercial vessels in those areas. Typical employers include operators of passenger and excursion vessels, towing and barge operations on inland waterways, harbor and utility work boats, and other small commercial fleets. The specific roles, pay and availability vary by region, employer and your other credentials and experience.
We do not publish earnings figures here because no verified number is established for this credential in our source material. For a qualitative look at the career side, read NM2GI Jobs, NM2GI Salary Guide 2026: Complete Earnings Analysis and Is the NM2GI Certification Worth It? Complete ROI Analysis 2026.
Your Approval to Test Is the Real Blueprint
The single most important practical point is that the NMC determines your individual assigned modules. Use your actual approval to test as the authority on what you will sit, not a forum post, a coworker's memory or a generic list.
- Check which rules module (Q100 or Q300) appears on your approval.
- Confirm whether you are on a full original route or an upgrade or raise-of-grade route.
- Match each assigned module to the published NMC topic matrix for that module.
On costs and scheduling, this site does not state current fees, since none are established in our verified source material. Because fees and logistics can change, confirm them directly with the NMC before you plan your budget. For context on what to expect, see NM2GI Certification Cost 2026: Complete Pricing Breakdown and NM2GI Exam Dates 2026: Testing Windows, Deadlines & Scheduling.
Likewise, no population pass rate or single passing-score figure is established here, so be cautious about any number presented as definitive. Our articles on NM2GI Pass Rate 2026: What the Data Shows and NM2GI Passing Score 2026: Exactly What You Need to Pass explain what can and cannot be said responsibly.
Sequencing Your Preparation Around the Modules
Generic study methods matter less than ordering your work around the actual modules. Here is a simple module-by-module sequence for a full-route candidate, adjustable to the time you have.
Rules of the Road (Q100 or Q300)
- Confirm which rules module applies on your approval
- Learn lights, shapes and signals first, since they are memorization-heavy
Deck General (Q340) and Deck Safety (Q341)
- Pair these because they share seamanship and safety foundations
- Use the NMC topic matrices as your checklist
Navigation General (Q342)
- Build the theory that Chart Plot will put into practice
Chart Plot (Q343) and mixed review
- Work plotting problems daily and review your errors
- Finish with timed practice across all assigned modules
Start Q343 practice lightly in week 2 if you are rusty, since that is the module that rewards repetition most. For fuller plans, see NM2GI Study Guide 2026: How to Pass on Your First Attempt, the quick-reference NM2GI Cheat Sheet 2026: One-Page Review of Must-Know Facts, and our NM2GI Training overview. When you are ready to test your recall, try the practice questions on the main NM2GI practice test site, or return to the NM2GI Exam Prep home page for module-by-module drills.
Frequently Asked Questions
It stands for National Master 200 GL and Inland, a U.S. Coast Guard National Maritime Center pathway under scope GLI05 for Master or Mate less than 200 GRT on Great Lakes and inland waters. It is unrelated to other credentials that share the acronym. See NM2GI Meaning for more.
Full-route preparation has five module groups: a rules module (Q100, or Q300 as an alternative on an applicable Inland route), plus Q340, Q341, Q342 and Q343. The count is not universal, because the NMC assigns modules individually.
No. They are alternatives. Great Lakes and Inland uses Q100, while Inland may use Q300 when the applicable COLREGS limitation is accepted. Never count them together.
No. Chart Plot Q343 is required in the full-exam structure and should not be omitted from your preparation, though your approval to test confirms your exact assigned modules.
No. Q345 is a separate raise-of-grade module from Master under 100 to Master or Mate under 200, and Q346 is a separate route from OUPV to Mate under 200. Neither is an extra domain on the Master-original route.