Conn. Gen. Stat. § 38a-344: (Formerly Sec. 38-175j). Proof of notice.

Proof of mailing by certified mail, return receipt requested, mail using the United States Postal Service intelligent mail barcode tracking method, as provided in Chapter 204 of the Domestic Mail Manual or any subsequent corresponding document of the United States Postal Service, or any similar tracking method developed by the United States Postal Service, or, if agreed between an insurer and a named insured, delivery by electronic means with proof of a delivery receipt, notice of cancellation, an intention not to renew or of reasons for cancellation, to the named insured and any third party designated pursuant to section 38a-323a at the address shown in the policy, or by electronic means if agreed between an insurer and a named insured, shall be sufficient proof of notice.