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It's the Law

Hull Identification Number


The Hull Identification Number (HIN) is a unique, 12-digit or 17-digit number assigned by the manufacturer to vessels built after 1972.

Hull Identification Numbers:

  • Distinguish one vessel from another.
  • Are engraved in the fiberglass or on a metal plate permanently attached to the transom.

You should write down your HIN and put it in a place separate from your vessel in case warranty problems arise or your vessel is stolen.

It is illegal to remove or in any way falsify a Hull Identification Number.

If your vessel is homemade, was built before 1972, or does not have a proper hull identification number (HIN), please contact the Massachusetts Environment Police at 1-800-632-8075 to arrange for a vessel inspection. The inspecting officer will provide the customer with an inspection certificate that must be presented when registering the vessel. At the time of registration, your boat will be assigned an HIN. You will be given instructions on how to place this HIN on your boat. You must provide proof, to the registration office, of the HIN placement on your boat before you will receive your registration card and decal.

The HIN is required to title and register your vessel.

Hull Identification Number