- NM2GI here means National Master 200 GL and Inland, issued through the U.S. Coast Guard National Maritime Center under scope GLI05.
- The full-route preparation has five module groups: Rules of the Road, Deck General, Deck Safety, Navigation General, and Chart Plot.
- Q100 and Q300 are alternatives for the Rules of the Road group, never two simultaneous requirements.
- Your NMC approval to test, not a generic checklist, determines which modules you must actually sit.
What Is NM2GI Certification?
- What the Credential Actually Is
- Who Issues It and What GLI05 Covers
- The Five Module Groups
- Q100 Versus Q300: Alternatives, Not Add-Ons
- Modules That Are Not Extra Domains
- Your Approval to Test Decides Your Modules
- Concrete Skills Candidates Must Master
- Who Hires License Holders
- Sequencing Your Preparation
- Frequently Asked Questions
Key Takeaways
- NM2GI here means National Master 200 GL and Inland, issued through the U.S. Coast Guard National Maritime Center under scope GLI05.
- The full-route preparation has five module groups: Rules of the Road, Deck General, Deck Safety, Navigation General, and Chart Plot.
- Q100 and Q300 are alternatives for the Rules of the Road group, never two simultaneous requirements.
- Your NMC approval to test, not a generic checklist, determines which modules you must actually sit.
- Chart Plot (Q343) is required in the full-exam structure and cannot be skipped in preparation.
What the Credential Actually Is
National Master 200 GL and Inland, abbreviated NM2GI on this site, is a U.S. mariner endorsement for operating vessels of less than 200 gross register tons on the Great Lakes and inland waters. The published scope code is GLI05, which the National Maritime Center describes as Master or Mate less than 200 GRT. It is a deck-officer credential, not a vendor certificate, and it sits inside the federal mariner credentialing system.
That distinction matters because the acronym is shared by several unrelated credentials elsewhere in the market. Everything in this article refers only to the Coast Guard deck endorsement. If you are comparing it against other qualifications, our overview pages such as What Is NM2GI? and What Does NM2GI Stand For? cover the naming in more detail.
Who Issues It and What GLI05 Covers
The governing body is the United States Coast Guard National Maritime Center (NMC). The NMC publishes its examination modules and topic matrices publicly, so the scope of what you will be tested on is not a secret. The relevant public pages are the Great Lakes and Inland endorsements page and the GLI05 page covering Master/Mate less than 200 GRT, along with the published deck and engineering examination guide.
One honesty note on sourcing: the guide document referenced for the module structure is the published version effective March 24, 2014, not a newly issued 2026 blueprint. Current indexed NMC matrices corroborate the same module headings, but you should always confirm against the live NMC pages and your own approval before finalizing a study plan.
The packet behind this article does not establish a single overall question count, a single exam duration, percentage weightings, current fees, or a population pass rate. Anyone quoting a precise pass rate or domain percentage for this endorsement is not working from published NMC data. For a careful look at what can and cannot be said about results, see NM2GI Pass Rate 2026: What the Data Shows.
The Five Module Groups
For full-route preparation, the content falls into five module groups. These are issuer-published modules, organized here as unweighted, route-aware preparation groups. Unweighted means we do not assign percentages, because none are established.
| Group | Module | Subject |
|---|---|---|
| 1 | Q100 (or Q300 on the restricted inland route) | Rules of the Road: Inland and International |
| 2 | Q340 | Deck General |
| 3 | Q341 | Deck Safety |
| 4 | Q342 | Navigation General: Great Lakes and Inland |
| 5 | Q343 | Navigation Problems: Chart Plot |
The exact full-route module sets are: Great Lakes and Inland uses Q100, Q340, Q341, Q342, and Q343 (five modules). Inland uses Q100 or Q300, plus Q340, Q341, Q342, and Q343 (also five modules). The published guide reference is section 2.1.2.3, printed page 27. For a domain-by-domain walkthrough, read NM2GI Exam Domains 2026: Complete Guide to All 5 Content Areas.
Q100 Versus Q300: Alternatives, Not Add-Ons
This is the single most common counting error. The Rules of the Road group is satisfied by one module or the other depending on your route:
- Great Lakes and Inland uses Q100.
- Inland may use Q300 when the applicable COLREGS limitation is accepted.
These are alternatives. They are not two extra domains, and they are never stacked on top of each other. If you see a study plan that lists both as simultaneous requirements and therefore claims six or seven modules, it has miscounted.
Domain 1: Rules of the Road (Q100 / Q300)
Inland and International rules, with the inland-only Q300 available as an alternative for the applicable restricted route.
- Know which rule set your route actually uses before you choose a module to prepare.
- Practice applying rules to vessel-encounter situations, not just reciting definitions.
- Be clear on the difference between the inland and international regimes, since the distinction is the heart of this group.
Modules That Are Not Extra Domains
The NMC also publishes modules tied to specific upgrade situations. These are easy to misread as part of the core five, so it is worth being explicit:
- Q345 (Navigation and Deck General/Safety) is a separate raise-of-grade module for candidates moving from Master less than 100 to Master/Mate less than 200.
- Q346 belongs to a separate route from OUPV to Mate less than 200. It is not an extra module for a Master-original applicant.
Separate upgrade, raise-of-grade, and route-extension modules are not additional full-original-exam domains. Likewise, the five-group figure is not a universal count of examinations for every applicant. Alternative Rules or Navigation General modules must never be counted together as simultaneous requirements.
Your Approval to Test Decides Your Modules
The NMC determines each individual's assigned modules. Two candidates who both say they are pursuing "NM2GI" may sit different module sets because of prior credentials, route, and any applicable limitations. The authoritative source is your actual approval to test, not an article, a forum thread, or a prep site, including this one.
Before you buy materials or commit to a schedule, read your approval line by line and map each assigned module to the preparation groups above. Eligibility and prerequisites are covered separately in NM2GI Requirements 2026: Eligibility, Prerequisites & How to Qualify, and the practical side of timing is in NM2GI Exam Dates 2026: Testing Windows, Deadlines & Scheduling.
On fees: this article does not quote current figures because none are established by the sources reviewed. Fee schedules change, so confirm them directly with the NMC. A broader discussion of the cost picture lives in NM2GI Certification Cost 2026: Complete Pricing Breakdown.
Concrete Skills Candidates Must Master
Deck General and Deck Safety (Q340, Q341)
Domains 2 and 3: Deck General (Q340) and Deck Safety (Q341)
These two groups cover the seamanship and safety knowledge expected of someone responsible for a vessel and its crew.
- Vessel handling, deck operations, and general seamanship practice.
- Safety equipment, emergency procedures, and shipboard safety responsibilities.
- The regulatory knowledge a master or mate of a vessel under 200 GRT is expected to carry.
Navigation General (Q342)
Domain 4: Navigation General: Great Lakes and Inland (Q342)
This group is tied to the waters you will operate on, which is why the Great Lakes and Inland framing is part of the module name.
- Piloting concepts, aids to navigation, and chart interpretation for the relevant waters.
- Weather, tides and currents, and other conditions that affect passage planning.
- Understanding how the Great Lakes and inland contexts differ from open-ocean practice.
Chart Plot (Q343)
Domain 5: Navigation Problems: Chart Plot (Q343)
Q343 is required in the full-exam structure and must not be omitted from your preparation, even if you feel strong in the theory groups.
- Working plotting problems accurately and methodically on a chart.
- Practicing under realistic conditions with the tools you will be permitted to use.
- Building speed without sacrificing accuracy, since plotting errors compound.
Chart plotting is a hands-on skill, so reading about it is not a substitute for working problems. Many candidates find this group the most demanding, which is explored in How Hard Is the NM2GI Exam? Complete Difficulty Guide 2026. Note that this site does not reproduce NMC sample questions and does not imply issuer endorsement of any practice material.
Who Hires License Holders
A master or mate endorsement for vessels under 200 GRT on the Great Lakes and inland waters is relevant wherever small commercial vessels operate. Typical employers include towing and barge operators, passenger and excursion vessel operators, ferry services, charter and sightseeing operations, and harbor and support-craft operators. Hiring depends heavily on region, season, and company, and this article does not state wage figures because none are established by the sources used. For a qualitative look at the work and earning picture, see NM2GI Jobs, NM2GI Salary Guide 2026: Complete Earnings Analysis, and Is the NM2GI Certification Worth It? Complete ROI Analysis 2026.
Sequencing Your Preparation
Rather than a generic plan, sequence the five groups by dependency. Rules of the Road underpins how you reason about every navigation scenario, so it comes first. Chart Plot is a practiced skill that benefits from repetition, so it should start early and recur. The sketch below assumes the full five-module route; adjust it to the modules in your approval to test.
Rules of the Road (Q100 or Q300)
- Confirm which rule module your route requires.
- Work encounter scenarios until the decision logic is automatic.
Deck General and Deck Safety
- Cover Q340 and Q341 together since the topics overlap in practice.
Navigation General and Chart Plot
- Study Q342 concepts, then immediately apply them in Q343 plotting problems.
Mixed review
- Rotate across all assigned modules and revisit your weakest group.
For a fuller approach, see the NM2GI Study Guide 2026: How to Pass on Your First Attempt, and keep the NM2GI Cheat Sheet 2026: One-Page Review of Must-Know Facts handy for final review. When you are ready to test your recall, the NM2GI practice tests let you drill each group, and you can return to the main practice site any time to track which areas still need work.
Key Takeaway
Build your plan from your approval to test, map each assigned module to the five preparation groups, and give Chart Plot (Q343) recurring hands-on practice rather than a single review pass.
Frequently Asked Questions
It refers to National Master 200 GL and Inland, a U.S. Coast Guard mariner endorsement under scope GLI05 for Master or Mate less than 200 GRT. It does not refer to any other credential sharing the abbreviation.
The United States Coast Guard National Maritime Center issues the endorsement and publishes the examination modules and topic matrices that define what candidates are tested on.
The full-route preparation has five module groups: Q100 (or Q300 on the applicable inland route), Q340, Q341, Q342, and Q343. That is not a universal count for every applicant, because the NMC assigns each individual's modules in the approval to test.
No. They are alternatives. Great Lakes and Inland uses Q100, while Inland may use Q300 when the applicable COLREGS limitation is accepted. They are never counted together as simultaneous requirements.
No. Q345 is a separate raise-of-grade module from Master less than 100 to Master/Mate less than 200, and Q346 is a separate OUPV-to-Mate less than 200 route. Neither is an additional module for a Master-original applicant.