NM1GI Requirements 2026: Eligibility, Prerequisites & How to Qualify

What This Credential Actually Covers

National Master 100 GL and Inland (NM1GI) is a mariner credential administered by the United States Coast Guard National Maritime Center (NMC). It corresponds to the NMC's GLI06 listing: Master or Mate of vessels less than 100 gross register tons (GRT), with Great Lakes and Inland waters scope. If you are searching for requirements, it helps to be clear about what this is. It is not a vendor certification or a multiple-choice credential from a private testing company. It is a federal merchant mariner credential, and the "requirements" are therefore shaped by Coast Guard regulation, NMC evaluation, and the approval you receive for your specific application.

If you are new to the terminology, our explainers on what NM1GI is and what NM1GI stands for cover the naming conventions. This article focuses on the practical question: what must be true of you, and of your application, before you can sit the examination modules?

Who Qualifies: Reading the Eligibility Picture

Eligibility for a Coast Guard deck credential is evaluated by the NMC against the applicable regulations, and the details depend on the applicant's circumstances. Rather than guess at a universal checklist, it is more useful to understand the categories of requirement the NMC evaluates and then confirm each against the current official guidance for your own application.

The categories the NMC evaluates

• Qualifying experience: Sea service or equivalent time that supports the grade and waters you are applying for.
• Personal and administrative requirements: Identity, citizenship or status, and the general application items the NMC requires for any merchant mariner credential.
• Safety and medical items: Fitness-for-duty and related documentation required for the credential.
• Examination or course-based demonstration of competence: Either passing the assigned examination modules or satisfying the requirement through an approved alternative where one applies to your case.

Exact thresholds, such as how much service you need and in what capacity, are set by regulation and applied by the NMC to your file. Because those figures depend on your route and prior credentials, confirm them directly against the NMC listing for GLI06 and your evaluation results rather than relying on secondhand summaries, including this one.

Why Approval to Test Controls Everything

The single most important concept in qualifying is the approval to test. After the NMC evaluates your application, it issues an approval that tells you exactly which examination modules you are assigned, which rules route applies, and whether any credit has been granted toward the exam. Two candidates pursuing the same credential can be assigned different module lists depending on prior credentials, route, and whether the application is a full original or a raise of grade.

This is also why you should treat any summary of "the" exam, including pass-rate discussions such as our look at what the data shows on NM1GI pass rates, as context rather than a prediction for your own module list. Official percentage weights are not published in the materials we draw on here, so any claim of a fixed percentage breakdown across topics should be treated with skepticism.

Route Choice: Inland vs. Great Lakes and Inland

Route is where the requirements become genuinely specific. The NMC's module-topic table distinguishes between topics that apply broadly and topics that apply only to the Great Lakes. Two points matter most:

• Rules of the Road depends on approved route. The rules module is either International and Inland (Q100) or Inland (Q300), according to the route approved for you. You sit one, not both. Count this as a single rules group in your preparation plan.
• Some deck topics are Great-Lakes-specific. In the NMC table, heavy-weather handling and the topic of maneuvering for launching lifeboats and liferafts in heavy weather carry a footnote marking them as Great-Lakes-specific. Whether those topics reach you depends on whether your approved route includes the Great Lakes.

If you are weighing whether an inland-only path or a Great Lakes and Inland path is right for your career, the answer also affects what you will need to learn. See our broader discussion in how hard the NM1GI exam is for how route scope influences difficulty.

The Five Preparation Groups You Must Qualify to Sit

For a full-route candidate, the published catalog organizes preparation into five groups, counting the route-specific rules choice once. These are unweighted preparation groups, not a single common mandatory examination: your own assigned modules come from your approval to test. The detailed treatment lives in our complete guide to the five NM1GI content areas; here is what each group asks of you from a requirements standpoint.

Notice that Domains 4 and 5 share much of their topic vocabulary. That overlap is intentional: Q349 tests your understanding, while Q350 tests your ability to execute the plot. Candidates who retain chart-plotting skill from day one tend to find the pairing easier, and our NM1GI study guide builds a schedule around that relationship.

Q352 and the Raise-of-Grade Route

A common point of confusion in qualification research is Q352, Navigation and Deck General/Safety. The NMC lists it as a separate raise-of-grade route module. It is not a universal sixth examination group that every full-original applicant must append, and it is not a second Rules subject. If your application is a full original, plan around the five groups above and the assignment in your approval to test. If you are raising the grade of an existing credential, your approval may instead list Q352, and you should prepare for exactly what it assigns.

Building Your Qualification File

Because the NMC evaluates a documented application, your qualification is only as strong as the paperwork behind it. Approach the file the way you would approach a navigation plan: gather the inputs early, check them for consistency, and leave margin for correction.

1. Confirm the credential and scope. Verify that GLI06 (Master or Mate less than 100 GRT) is the listing you intend, and that your intended waters match Great Lakes and Inland scope.
2. Collect service documentation. Gather records that demonstrate the sea service the NMC will evaluate for your route.
3. Assemble personal and medical items. Complete the administrative and fitness requirements the NMC lists for merchant mariner credentials generally.
4. Submit and await evaluation. The NMC reviews the file and, if you are eligible, issues your approval to test.
5. Read the approval line by line. Note the exact module codes, the rules route, and any credit awarded before you begin serious preparation.

Fee mechanics follow the NMC's published schedule for credential evaluation and issuance, and examination-related costs depend on how and where you test. We do not quote specific dollar figures here because they change; our NM1GI certification cost breakdown explains how to think about the cost categories, and the NMC remains the authoritative source for current amounts. Scheduling follows a similar logic: testing locations and availability vary, so see NM1GI exam dates and scheduling for how to approach timing.

Sequencing Your Preparation Around the Requirements

Generic study advice is plentiful. What is specific to this credential is the order in which the five groups reward your effort. The following outline ties the sequence to the actual content:

Adjust the pacing to your own assignment and background; the point is the dependency order, not the calendar. For a fast recap of high-yield facts once you are deep into review, keep our NM1GI cheat sheet nearby, and use the NM1GI practice test site to rehearse question recall under realistic conditions.

Who Hires Holders of This Credential

A Master or Mate credential for vessels under 100 GRT on Great Lakes and Inland waters points toward operators of smaller commercial vessels on those waters. Typical employers in this space include passenger and excursion operators, charter and small-vessel services, towing and harbor-work operators, and other businesses running sub-100-GRT vessels on inland and Great Lakes routes. Specific openings and pay vary widely by operator, season, and vessel type, so we avoid quoting figures. If you are evaluating the career side of the decision, our pieces on NM1GI jobs, the NM1GI salary guide, and whether the certification is worth it take that analysis further.

For readers who want the broader orientation before committing, the NM1GI certification overview and our NM1GI training page outline the learning pathways, and the passing score article addresses how the result is determined.

Frequently Asked Questions