Credentials & Recognition
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Authored by Instructors Rich Adler
Licensed Guide · Published September 15, 2026
A captain’s license is a credential the U.S. Coast Guard (USCG) issues that lets the holder operate a commercial vessel. The two main licenses are the OUPV/Six-Pack and the 25/50/100 Ton Master’s. You can add endorsements for inspected sailing vessels or assistance towing.
A captain’s license is a USCG Merchant Mariner Credential that clears you to run a commercial vessel, and you earn it by passing an exam and meeting a set of requirements. Those requirements include a physical and drug test, a minimum amount of boating experience, and a background check.
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A USCG captain’s license is a Merchant Mariner Credential (MMC) for operating a commercial vessel for hire. The two main types are the OUPV/Six-Pack, for up to six paying passengers, and the 25/50/100 Ton Master’s, for inspected vessels carrying seven or more. You need one once a passenger pays.
Most people who land on this page are trying to answer one question: Do I actually need a captain’s license, and if so, which one? The rules can feel murky, but the line is clearer than you’d think.
We’ve helped more than 200,000 students sort this out, and it usually comes down to whether you carry paying passengers and how many. Here’s a plain-language guide to the types, when the law requires one, and how the two licenses differ.