SUPPLEMENT DATED MARCH 1, 2013

to

TO PROSPECTUS DATED DECEMBER 31, 2003

FOR KEYLIFE

ISSUED BY SUN LIFE ASSURANCE COMPANY OF CANADA (U.S.)

KEYPORT VARIABLE ACCOUNT I

Pursuant to Board of Trustee and shareholder approval, effective at the close of business on April 26, 2013, Columbia Variable Portfolio – Money Market Fund will merge into Columbia Variable Portfolio – Cash Management Fund.

Please retain this supplement with your prospectus for future reference.