Conn. Agencies Regs. § 9-32-2
The registrars shall send to each elector a notice of canvass by first class mail to the residence of such elector as shown on the last completed registry list for the municipality. The notice of canvass shall be on a form on which the elector may furnish information to enable the registrars to correct the registry list as it pertains to such elector. The registrars shall include with the notice a postage paid envelope for the return of the notice, or the notice may be in the form of a post card which is returnable postage paid. For purposes of these regulations, "last completed registry list" means the registry list for the municipality including any changes, additions and deletions made on or before the date when the notice of canvass is sent to the elector.
Conn. Agencies Regs. § 9-32-2