46 CFR 11.452: Master of Great Lakes and inland vessels under 200 GRT
Last reviewed: October 14, 2026
This section sets the service needed to qualify for an endorsement as Master of Great Lakes and inland self-propelled vessels of less than 200 GRT. The minimum is 1 year of service on vessels, with part of it in a Master, Mate, or equivalent position. Separate service is needed for sail or auxiliary sail authority.
Applies toApplicants for an endorsement as Master of Great Lakes and inland self-propelled vessels of less than 200 GRT.
What it says
An applicant must have at least 1 year of service on vessels to qualify for the endorsement.
46 CFR 11.452(a)“is 1 year of service on vessels”
Six months of the required service must have been as Master, Mate, or equivalent position while holding an endorsement as Master or Mate of self-propelled vessels, or Master or Mate (Pilot) of Towing Vessels, or OUPV.
46 CFR 11.452(a)“Six months of the required service must have been as Master, Mate, or equivalent position while holding an endorsement as Master or Mate of self-propelled vessels, or Master or Mate (Pilot) of Towing Vessels, or OUPV.”
To obtain authority to serve on the Great Lakes, 3 months of the required service must have been on Great Lakes waters.
46 CFR 11.452(a)“To obtain authority to serve on the Great Lakes, 3 months of the required service must have been on Great Lakes waters”
Without that Great Lakes service, the endorsement will be limited to the inland waters of the United States (excluding the Great Lakes).
46 CFR 11.452(a)“otherwise the endorsement will be limited to the inland waters of the United States (excluding the Great Lakes).”
To obtain an endorsement for sail or auxiliary sail vessels, the applicant must have 6 months of service on sail or auxiliary sail vessels.
46 CFR 11.452(b)“To obtain an endorsement for sail or auxiliary sail vessels, the applicant must have 6 months of service on sail or auxiliary sail vessels.”
The sail or auxiliary sail service may have been obtained before the MMC endorsement as Master was issued.
46 CFR 11.452(b)“This required service may have been obtained prior to issuance of the MMC endorsement as Master.”
Common questions
How much service do I need for Master of inland vessels under 200 GRT?
The minimum is 1 year of service on vessels. Six months of it must have been as Master, Mate, or equivalent position under the listed endorsements.
“is 1 year of service on vessels”
How do I get Great Lakes authority on this Master endorsement?
Three months of the required service must have been on Great Lakes waters. Otherwise the endorsement is limited to inland waters of the United States, excluding the Great Lakes.
“To obtain authority to serve on the Great Lakes, 3 months of the required service must have been on Great Lakes waters”
What service is needed for a sail or auxiliary sail endorsement?
The applicant must have 6 months of service on sail or auxiliary sail vessels. That service may have been obtained before the MMC endorsement as Master was issued.
“This required service may have been obtained prior to issuance of the MMC endorsement as Master.”
The text of 46 CFR 11.452
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 less than 200 GRT
(a) The minimum service required to qualify an applicant for an endorsement as Master of Great Lakes and inland self-propelled vessels of less than 200 GRT is 1 year of service on vessels. Six months of the required service must have been as Master, Mate, or equivalent position while holding an endorsement as Master or Mate of self-propelled vessels, or Master or Mate (Pilot) of Towing Vessels, or OUPV. To obtain authority to serve on the Great Lakes, 3 months of the required service must have been on Great Lakes waters; otherwise the endorsement will be limited to the inland waters of the United States (excluding the Great Lakes).
(b) To obtain an endorsement for sail or auxiliary sail vessels, the applicant must have 6 months of service on sail or auxiliary sail vessels. This required service may have been obtained prior to issuance of the MMC endorsement as Master.
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.