The 26-times capped Scotland centre is one of six senior players who will be moving on. Johnson, 29, joined Glasgow from Queensland Reds in 2015 and made 104 appearances. He was out for a spell this season after suffering a broken jaw against the Sharks in October but returned to the side and has started 11 matches at inside centre in what has been a successful campaign for the Warriors who are through to the European Challenge Cup final, against Toulon in Dublin on May 19.
Also leaving the club are former captain Ryan Wilson, whose departure after 13 years with Glasgow was confirmed last month, second row Lewis Bean, wing Cole Forbes, prop Simon Berghan and flanker Cameron Neild.
Franco Smith, the Warriors head coach, paid tribute to the departing players, saying: “Thank you to Ryan, Sam, Lewis, Cole, Simon and Cameron for their contributions to the club this season. I am grateful for their hard work, and wish them all the very best in their new challenges. After a season like this it is difficult to say goodbye to players that bought in and contributed the way they did. They have all played a valuable part in helping us to reach the league quarter-finals, and will keep doing so as we continue preparations for our first ever European final. I sincerely thank these players for their commitment to the Glasgow Warriors team and the club’s values.”