WHAT VESSELS MAY BE DOCUMENTED?
A vessel must measure at least five net tons and, with the exception of certain oil spill response vessels, must be wholly owned by a citizen of the U.S.
HOW DO I KNOW IF MY VESSEL MEASURES FIVE NET TONS?
Net tonnage is a measure of a vessel's volume. It should not be confused with the vessel's weight, which may also be expressed in tons. Most vessels more than 25 feet in length will measure five net tons or more. For information about how tonnage is determined, including a web-based interactive form that calculates tonnages, visit the U.S. Coast Guard Marine Safety Center's web site at the Marine Safety Center's Tonnage Page.
WHAT ARE THE VESSEL NAME AND HAILING PORT MARKING REQUIREMENTS?
Documented vessels do not display their official numbers on the outside of the hull, but are identified by the name and hailing port. The application for documentation must include a name for the vessel composed of letters of the Latin alphabet or Arabic or Roman numerals and may not exceed 33 characters. The name may not be identical, actually or phonetically, to any word or words used to solicit assistance at sea; may not contain or be phonetically identical to obscene, indecent, or profane language, or to racial or ethnic epithets. Once established, a vessel's name may not be changed without application, fees, and the consent of the Director, National Vessel Documentation Center. There is no rule against duplication of names for documented vessels, so hailing ports are helpful in identifying vessels.
HOW DO I MARK MY VESSEL?
The official number assigned to documented vessels, preceded of the abbreviation "NO." must be marked in block-type Arabic numerals at least three inches high on some clearly visible interior structural part of the hull. The number must be permanently affixed so that alteration, removal, or replacement would be obvious and cause some scarring or damage to the surrounding hull area.
The name and hailing port of a recreational vessel must be marked together on some clearly visible exterior part of the hull. The vessel name of a commercial vessel must also be marked on the port and starboard bow and the vessel name and the hailing port must also be marked on the stern. All markings may be made by any means and materials that result in durable markings and must be at least four inches in height, made in clearly legible letters of the Latin alphabet or Arabic or Roman numerals. The "hailing port" must include both a place and a State, Territory, or possession of in the United States. The state may be abbreviated.