USCG hierarchy of waters

The hierarchy of USCG waters is Oceans -> Near Coastal -> Great Lakes, -> Inland. There are some exceptions for towing and Western Rivers.

What does this mean?

From 46 CFR 11

Oceans

Subject to provisions about Western Rivers, any license or MMC endorsement for service as master or mate on ocean waters qualifies the mariner to serve in the same grade on any waters, except towing vessels upon western rivers subject to the limitations of the endorsement.

Near Coastal

Subject to provisions about Western Rivers, any license or MMC endorsement issued for service as master or mate on near-coastal waters qualifies the mariner to serve in the same grade on Great Lakes and inland waters, except towing vessels upon western rivers subject to the limitations of the endorsement.

Great Lakes

Any officer endorsement issued for service on Great Lakes and inland waters self-propelled vessels, excluding towing vessels, is valid on all of the inland waters of the United States

Inland

Any officer endorsement issued for service on inland waters self-propelled vessels, excluding towing vessels, is valid for the inland waters of the United States, excluding the Great Lakes.

We hope this made your life a little easier and if you have other questions the MM-SEAS team is always here to help!

We do prefer to answer questions live with screen sharing to make both of our lives easier.

We hold free live virtual office hours Monday and Wednesday from 5:00 - 5:30 pm PT inside of mmseas.com under License Guidance and then Daily Office Hours.

Pro MM-SEAS members get access to our daily live office hours Monday thru Friday from 5:00 - 5:30 pm PT. You also get access to unlimited live 1 on 1 calls with one of our USCG Licensing Specialists. Pro MM-SEAS members can access these features inside of mmseas.com under License Guidance.