US Weekly reported the couple made the announcement and celebrated with a party in Prince Edward Island.
Phaneuf, 27, played for the Calgary Flames from 2005-10, before he was traded to Toronto.
Cuthbert, 29, is a native of the Alberta city. She is best known for her role on the TV series "24" and currently is among the cast of the sitcom "Happy Endings."
The couple has been dating since 2008.