DMV has a field to enter the SBC when you register a boat, but it's not required. You can buy a car without a driver's license, you just can't drive it. You can buy a boat without a SBC, you just can't drive it.

http://www.ct.gov/dmv/cwp/view.asp?a=817&Q=245288&dmvPNavCtr=|#27864

Below listed are the documents required for the registration of a boat. However, please be sure to read each scenario so that you will have all the proper documentation based upon where the boat was purchased.

A. Application for Vessel Registration and Certificate of Number or Decal (form B-148) (Download, fill out online and print this form.)

B. Bill of Sale (form H-31).

C. Proof of payment of Sales and Use Tax:

Complete applicable information in Tax Exemptions Section of the Application for Vessel Registration and Certificate of Number or Decal (form B-148).

Boats Purchased from a Dealer

A "paid in full" Bill of Sale (form H-31) must be submitted showing amount paid and amount of sales tax collected by the dealer.
If purchased from an out-of-state dealer, a credit of the sales tax paid is allowed. However, the total sales tax must equal the 6.35 percent Connecticut Sales Tax for vessels purchased at $100,000 or less. In addition, the sales tax will be 7 percent for vessels over $100,000. A receipt must be shown.

Boats Purchased from an Individual

A Bill of Sale (form H-31) signed by the seller must be submitted showing amount paid. At the time of registration a 6.35 percent Connecticut sales tax will need to be paid for vessels purchased at $100,000 or less. In addition, the sales tax will be 7 percent for vessels over $100,000. If the seller is not the last registered owner, each Bill of Sale (form H-31) must be submitted for each ownership transfer back to the last registered owner.
A completed Application for Vessel Registration and Certificate of Number or Decal (form B-148). (Download, fill out online and print this form.)
A letter of explanation if the boat was never registered, as well as a completed Ownership Affidavit (form B-203).

Certificate of Decal

A copy of the Coast Guard documentation with the Application for Vessel Registration and Certificate of Number or Decal (form B-148). The document must be current and issued in the name of the applicant. (Download, fill out online and print this form.)
If registered out-of-state, a current copy of the out-of-state registration must be submitted with the Application for Vessel Registration and Certificate of Number or Decal (form B-148).

Note:

You do not have to be a Connecticut resident to register your vessel in Connecticut. If the vessel is being used in Connecticut waters for more than 60 days, you must apply for a certificate of decal.

Sec. 15-142. Vessel numbering requirements. Certain vessels required to display registration decals.
(a) Every vessel used upon the waters of this state shall be numbered, except as otherwise provided in this section and section 15-143. For purposes of this section and said section 15-143, any launching, mooring or operation of a vessel upon the waters of this state shall be deemed to be a use of such vessel upon the waters of this state. No person shall launch, moor or operate and no owner shall permit the launching, mooring or operation of any vessel unless (1) the owner holds a valid, effective certificate of number awarded by this state or by the United States or by another state pursuant to the provisions of the federal Boat Safety Act of 1971 and the identification number set forth in such certificate is displayed on each side of such vessel at the bow, (2) the owner holds a valid marine document issued by the United States Coast Guard or (3) such vessel is otherwise not required to be numbered in this state under the provisions of said section 15-143. (b) Each vessel with respect to which the owner holds a valid marine document issued by the United States Coast Guard, a valid certificate of number awarded by the United States pursuant to the provisions of the federal Boat Safety Act of 1971 or a valid certificate of number awarded by another state, which vessel is used upon the waters of this state for more than sixty days in any calendar year, shall be required to display a Connecticut registration decal. No person shall launch, moor or operate and no owner shall permit the launching, mooring or operation of any such vessel unless (1) the owner holds a valid, effective certificate of registration awarded by this state and (2) the registration decal is
displayed as directed by the Commissioner of Environmental Protection, provided the requirements of this subsection shall not be applicable, in the period commencing on the first day of October in any year to and including the thirtieth day of April next succeeding, to any such vessel in use upon the waters of this state exclusively for purposes of delivery of such vessel to a facility in this state for storage, including dry storage and storage in water by means of apparatus preventing ice damage to the hull, maintenance or repair or the actual process of storage, maintenance or repair of such vessel.

Sec. 15-144. Vessel registration number or registration decal. Schedule of fees payable to Commissioner of Motor Vehicles. Regulations. Penalty. (a) Any owner desiring to obtain a vessel registration number or registration decal shall apply to the Commissioner of Motor Vehicles and shall file such proof of ownership of the vessel as the commissioner may require. Upon receipt of an application in proper form and the numbering fee, the Commissioner of Motor Vehicles shall assign a registration number or registration decal and provide the owner with a temporary certificate of number or temporary certificate of decal. The Commissioner of Motor Vehicles shall issue two registration decals and a permanent certificate. A registration decal shall be displayed on each side of the vessel at the bow in a manner prescribed by the Commissioner of Energy and Environmental Protection. The certificate shall state the name of the owner, his address, a description of the vessel, its hull identification number, the expiration date of the certificate and such other information as the Commissioner of Energy and Environmental Protection may prescribe by regulations. Such certificate shall be carried aboard and shall be available for inspection upon the vessel for which it is issued whenever the owner or any person authorized by him is aboard such vessel, except that the certificate of number for a vessel which is less than twenty-six feet and which is rented for noncommercial purposes for less than twenty-four hours may be retained on shore by the owner of such vessel or his agent at the place where such vessel departs or returns. If such certificate is retained on shore, a rental agreement signed by the owner or his agent and by the person renting the vessel shall be carried aboard such vessel and shall be available for inspection. Such rental agreement shall contain the vessel number which appears on the certificate of number and the length of time for which such vessel is rented.

Takes effect October 1, 2013.

The Colonel just emailed it all out to us the other day. I sent it to all my officers in the West on either Friday or Monday.