Coyle played part of a single season with the Saint John Sea Dogs of the Quebec Major Junior Hockey League (QMJHL) in 2012.

[4] On December 16, 2011, Coyle made the decision to leave Boston University and sign with the Saint John Sea Dogs of the Quebec Major Junior Hockey League (QMJHL).

[6] On March 1, 2012, Coyle signed a three-year, entry-level contract with the Wild, with the team keeping him in the QMJHL with the Saint John Sea Dogs until the end of the 2011–12 season.

Charlie made headlines after making a fan named Henry's dreams come true after waving to the boy during warm-ups.

Early in the 2017–18 season, Coyle was placed on long-term injury reserve after breaking his leg in a game against the Chicago Blackhawks.

[14] In a game against the New York Rangers on February 13, 2018, a puck caught him high on the mouth, requiring stitches to close it.

[15] On February 20, 2019, Coyle was traded to the Boston Bruins in exchange for Ryan Donato and a fifth-round pick in the 2019 NHL Entry Draft.

[16][2] Although Coyle initially struggled with the Bruins, totaling 2 goals and 4 assists playing 21 regular season games, he was able to find consistency in time for the 2019 playoffs, centering the Bruins' third line now wearing lucky number 13 along with Marcus Johansson and Danton Heinen, scoring 9 goals and 16 points in 24 games.

[22][23][24] In August 2021, Coyle proposed to his long-time girlfriend Danielle Hooper, former Miss Minnesota USA 2013.