[9] By the conclusion of the 2010–11 season, Andreoff earned a scholarship to attend Durham College[10] and received the teams' Eric Lindros Top Forward Award.

[11] Prior to the beginning of the following season, Andreoff signed a three-year entry-level contract with the Kings on October 13, 2011, before being loaned back to the Generals.

[13] Upon concluding his major junior career, Andreoff was reassigned to the Kings' American Hockey League (AHL) affiliate, the Manchester Monarchs, for the remainder of the season on an amateur tryout agreement.

[21] Andreoff signed a two-year, $1.5 million contract as an unrestricted free agent with the Philadelphia Flyers on July 1, 2019.

Following his second season within the Islanders organization in 2022–23, Andreoff mutually terminated the remaining year of his contract with New York after he was placed on unconditional waivers on July 6, 2023.

[25] As a free agent, Andreoff signed his first contract abroad in agreeing to a one-year deal with Russian club, HC Sibir Novosibirsk of the Kontinental Hockey League (KHL), on July 10, 2023.