46 CFR 11.433: Master of Great Lakes and inland vessels, unlimited tonnage

Last reviewed: October 14, 2026

This section sets the minimum service an applicant needs for an endorsement as Master of Great Lakes and inland self-propelled vessels of unlimited tonnage. It lists three ways to qualify. Paragraph (b) is reserved.

Applies toApplicants for an endorsement as Master of Great Lakes and inland self-propelled vessels of unlimited tonnage.

What it says

  1. An applicant can qualify with one year of service as a Mate or First-Class Pilot acting as First Mate of Great Lakes self-propelled vessels of 1,600 GRT or more, while holding an MMC endorsement as Mate inland or First-Class Pilot of Great Lakes and inland self-propelled vessels of unlimited tonnage.

    46 CFR 11.433(a)(1)“One year of service as a Mate or First-Class Pilot while acting in the capacity of First Mate of Great Lakes self-propelled vessels of 1,600 GRT or more”

  2. An applicant can instead qualify with two years of service as Master of self-propelled vessels of 1,600 GRT or more on inland waters, excluding the Great Lakes.

    46 CFR 11.433(a)(2)“Two years of service as Master of self-propelled vessels of 1,600 GRT or more on inland waters, excluding the Great Lakes; or”

  3. An applicant can instead qualify with one year of service upon Great Lakes waters while holding an MMC endorsement as Mate or First-Class Pilot of Great Lakes and inland self-propelled vessels of 1,600 GRT or more.

    46 CFR 11.433(a)(3)“One year of service upon Great Lakes waters while holding an MMC endorsement as Mate or First-Class Pilot of Great Lakes and inland self-propelled vessels of 1,600 GRT or more.”

  4. Under the one-year Great Lakes option, at least 6 months of the service must have been as First Mate.

    46 CFR 11.433(a)(3)“A minimum of 6 months of this service must have been in the capacity of First Mate.”

  5. Under that option, Second Mate service is accepted for the remainder on a two-for-one basis, up to a maximum of 6 months, where 2 days of service equals 1 day of creditable service.

    46 CFR 11.433(a)(3)“Service as Second Mate is accepted for the remainder on a two-for-one basis to a maximum of 6 months (2 days of service equals 1 day of creditable service).”

Common questions

How much service do I need to be Master of Great Lakes and inland vessels of unlimited tonnage?

The section gives three routes: one year as First Mate service, two years as Master on inland waters, or one year on Great Lakes waters as Mate or First-Class Pilot. Each route has its own conditions.

“Two years of service as Master of self-propelled vessels of 1,600 GRT or more on inland waters, excluding the Great Lakes; or”

Does Second Mate service count toward Great Lakes Master service?

Yes, under paragraph (a)(3) it is accepted for the remainder after 6 months as First Mate, on a two-for-one basis up to a maximum of 6 months.

“Service as Second Mate is accepted for the remainder on a two-for-one basis to a maximum of 6 months (2 days of service equals 1 day of creditable service).”

Does inland Master service include time on the Great Lakes?

No. The two-year Master service option applies to inland waters, excluding the Great Lakes.

“Two years of service as Master of self-propelled vessels of 1,600 GRT or more on inland waters, excluding the Great Lakes; or”

The text of 46 CFR 11.433

Electronic Code of Federal Regulations (eCFR), current as of April 16, 2026 · Read it on eCFR

Requirements for Master of Great Lakes and inland self-propelled vessels of unlimited tonnage

(a) The minimum service required to qualify an applicant for an endorsement as Master of Great Lakes and inland self-propelled vessels of unlimited tonnage is—

(1) One year of service as a Mate or First-Class Pilot while acting in the capacity of First Mate of Great Lakes self-propelled vessels of 1,600 GRT or more while holding an MMC endorsement as Mate inland or First-Class Pilot of Great Lakes and inland self-propelled vessels of unlimited tonnage;

(2) Two years of service as Master of self-propelled vessels of 1,600 GRT or more on inland waters, excluding the Great Lakes; or

(3) One year of service upon Great Lakes waters while holding an MMC endorsement as Mate or First-Class Pilot of Great Lakes and inland self-propelled vessels of 1,600 GRT or more. A minimum of 6 months of this service must have been in the capacity of First Mate. Service as Second Mate is accepted for the remainder on a two-for-one basis to a maximum of 6 months (2 days of service equals 1 day of creditable service).

(b) [Reserved]

The plain-English explanation on this page was written with AI from the regulation text above and checked automatically before publishing: every quote appears in the text, every number comes from it, and a second model confirmed each statement adds nothing the text doesn't say. Regulation text current as of April 16, 2026. The regulation text governs. RegKnot is not affiliated with the U.S. Coast Guard.