Andrighetto had five goals and 11 assists for the Avalanche after being acquired in a trade with Montreal on March 1.
The 24-year-old Andrighetto was a third-round pick by Montreal in the 2013 draft. He bounced between the Canadiens and the American Hockey League's St. John's IceCaps before being dealt to the Avalanche, where he led the team in scoring for March.
Avalanche general manager Joe Sakic says Andrighetto "sees the ice well and brings speed and scoring to our lineup."
Colorado missed the playoffs for a third straight season.
The Avalanche announced Andrighetto's contract on Wednesday.