The different types of captains licenses

OUPV Inland (6 PAK) - Uninspected Passenger Vessel Operator

6 paying passengers plus crew
License is good up to 100 Gross Tons
The vessel must be operated within the US Coast Guard dedicated boundary lines
Time is not required outside the US Coast Guard dedicated boundary lines to obtain the license
Must be a minimum of 18 years of age to be an operator
To operate a vessel of less than 5 net tons, around 26ft, you do not need to be a US citizen. It is required to be a US citizen when operating a documented vessel for hire over 5 net tons.
Transportation Worker Identification Credential (TWIC Card)

6 paying passengers plus crew
License is good up to 100 Gross Tons
A licensed captain is often required for deliveries and relocations by the insurance companies.
Operating vessels inland and up to 100 miles offshore
STCW training could be required when operating in international waters and traveling to international ports.
Must be a minimum of 18 years of age to be an operator
To operate a vessel of less than 5 net tons, around 26ft, you do not need to be a US citizen. It is required to be a US citizen when operating a documented vessel for hire over 5 net tons.
Transportation Worker Identification Credential (TWIC Card)

Vessels are permitted to carry more than 6 passengers with the maximum number of passengers regulated by the vessel certificate of inspection.
Based on experience the US Coast Guard assigns the tonnage rating
A licensed captain is often required for deliveries and relocations by insurance companies
The vessel must be operated within the US Coast Guard dedicated boundary lines
Time is not required outside the US Coast Guard dedicated boundary lines to obtain the license
Must be a minimum of 19 years of age to be an operator
You must be a US citizen to obtain and hold a Master's license
Transportation Worker Identification Credential (TWIC Card)

Vessels are permitted to carry more than 6 passengers with the maximum number of passengers regulated by the vessel certificate of inspection.
The US Coast Guard assigns the tonnage rating based on your operation of the similar vessels you've operated in the past three years
The vessel must be operated within the US Coast Guard dedicated boundary lines
Must be a minimum of 19 years of age to be an operator
You must be a US citizen to obtain and hold a Master's license
Within the authorization of OUPV endorsement, uninspected vessels can be operated up to 100 miles from shore
A UPV vessel can carry up to 6 paying passengers and crew
Within the OUPV portion of your masters license is good up to 100 gross tons.
A licensed captain is often required for deliveries and relocations by the insurance companies
STCW training could be required when operating in international waters and traveling to international ports.
Transportation Worker Identification Credential (TWIC Card)

Holds the same authority as the Master Inland / OUPV, in addition allows the operator to act as a mate on inspected vessels up to 200 miles offshore and also allows the holder to operate uninspected vessels up to 200 miles offshore.
Master Near Coastal 25, 50 or 100 Gross Ton
Vessels are permitted to carry more than 6 passengers with the maximum number of passengers regulated by the vessel certificate of inspection.
Based on experience the US Coast Guard assigns the tonnage rating
A licensed captain is often required for deliveries and relocations by the insurance companies
Both inspected and uninspected vessels an be operated inland and up to 200 miles offshore
STCW training could be required when operating in international waters and traveling to international ports.
Must be a minimum of 19 years of age to be an operator
You must be a US citizen to obtain and hold a Master's license
Transportation Worker Identification Credential (TWIC Card)