The 2008–09 Calgary Flames season was the 29th season for the Calgary Flames, and the 37th for the Flames franchise in the National Hockey League (NHL). The Flames finished second in the Northwest Division, and qualified for the 2009 Stanley Cup Playoffs as the fifth seed in the Western Conference, their fifth consecutive appearance in the post season. Their season ended when they were defeated by the Chicago Blackhawks in the Western Conference quarter-finals.

The 2009 Stanley Cup playoffs of the National Hockey League began on April 15, 2009, after the 2008–09 regular season. The sixteen teams that qualified, eight from each conference, played a best-of-seven series for the conference quarterfinals, semifinals, and championships, and then the conference champions played a best-of-seven series for the Stanley Cup. The Columbus Blue Jackets made their first appearance in the playoffs in their nine-year history. Previously they had been the only franchise never to have made the playoffs. Also, home teams set a record by going 13–2 in the openers of all the series combined. There were no playoff games played in the Province of Ontario as this was the first time that the modern Ottawa Senators and the Toronto Maple Leafs both missed the playoffs in the same year. This was the most recent time that the Carolina Hurricanes were in the playoffs until 2019.