Boat Registration

Connecticut law requires that all boats with motors, regardless of size, and sailboats powered by sail alone, 19 1/2 feet or longer in length, be registered and numbered before launching. If you purchase a boat that is currently registered, you are responsible for seeing that it is registered in your name.

All vessels must be registered with the Department of Motor Vehicles (DMV). Evidence of ownership must be submitted at the time of registration. Upon receipt of the application and fee, an identification number will be assigned and a certificate of number/registration will be issued along with two validation decals. The registration will be valid until April 30 of the following year. Connecticut vessel numbers stay with the boat as long as it is registered in the state.

Normally you will receive a registration renewal from DMV early in the calendar year. If you do not register the boat for a year, you will not receive another renewal notice and you must go to a DMV office to renew your registration.

Abandoned Boats
In Connecticut, a boat is considered abandoned if it is:
  • Left on someone’s property for more than 24-hours without the property owner’s permission;
  • Found free floating and unattended on the waters of the state for more than 24-hours;
  • Improperly registered and left on the waters of the state for more than 24-hours;
  • Left at a mooring for more than sixty days since payment for the mooring became overdue;
  • Left at a commercial facility for more than one year since payment for storage became overdue; or,
  • Found during a declared public emergency in a public right-of-way.
Additional information on the process for claiming abandoned boats.


Position of Vessel Number and Decals

The numbers, which must be at least three inches high, contrasting in color to the background and of block form, must be painted on or attached to both the port and starboard bow so positioned as to be distinctly visible and legible from at least 100 feet away. The two validation decals must be placed two inches to the right of and in line with the assigned boat number. No other numbers and only current decals shall be displayed.

Certificate to Be On Board

A certificate of number/registration or certificate of decal/registration must be on board the vessel whenever the owner or any person authorized by the owner is aboard, except that rented boats may carry a rental agreement in lieu of a certificate.

Hull Identification Number

The Hull Identification Number (HIN) is a unique 12-14 digit number (numbers and letters) assigned by the manufacturer to boats built after 1972. (Like the Vehicle Identification Number / VIN on a car.) It is attached or engraved to the upper right hand corner of the exterior transom.

How to Obtain a Hull Identification Number (HIN):

Complete the Application for Connecticut Vessel Hull Identification Number and return it to: 333 Ferry Road in Old Lyme, CT 06371.

When completeing the Application for a Hull Identification Number:
  1. Type or print the information requested.
  2. Print legibly when handwritten.
  3. Remember to sign and date the application.
Once completed, either mail or deliver in person the completed application for a Hull Identification Number to:
Department of Energy and Environmental Protection
Boating Division Hull Identification Unit
333 Ferry Road
P.O. Box 280
Old Lyme, CT 06371-0280

Frequently Asked Questions regarding Boating Registration and Hull Identification Numbers


For further information on boating regulations, please contact the Boating Division by e-mail at, or by telephone at 860-434-8638.

Content last updated December 16, 2019