Mitch Fadden's junior career began with the Seattle Thunderbirds organization after being selected in the 5th round, 82nd overall, in the 2003 WHL Bantam Draft. He played in 2 games in 2003-2004 for Seattle going scoreless. In 2004-2005 he played his first full season of junior scoring 9 goals and 21 points in 64 games with 30 penalty minutes. In 12 playoff games he also scored 2 goals with 4 penalty minutes and at season's end he was being touted as one of the WHL's top prospects for the 2006 NHL Draft. Unfortunately, Fadden had a horrible 2005-2006 season that saw him dealt by Seattle at midseason to Lethbridge. In total, the listless Fadden had 20 goals and 48 points in 68 games with 41 penalty minutes and despite a strong playoffs in which he scored 2 goals and 7 points in 6 games with 14 penalty minutes his stock plummetted. Fadden was ranked 126th among North American skaters by NHL Central Scouting and was passed over in the 2006 NHL Entry Draft. In the offseason he was invited to attend rookie camp with the New York Rangers before returning to Lethbridge. The change of scenery suited Fadden and he had 36 goals and 84 points in 71 games with 54 penalty minutes finishing 7th in the WHL in scoring. At year's end he had risen to 51st among North American skaters according to NHL Central Scouting and was selected by the Lightning in the 4th round, 107th overall, in the 2007 NHL Entry Draft. At the start of the 2007-2008 season, Fadden attended his first Traverse City Prospect Tournament for the Lightning and finished tied for second on the team in scoring with 2 goals and 4 points in 4 games to go with 4 penalty minutes and a +4 rating. After the tournament, Fadden returned to Lethbridge where he posted another impressive season in the WHL. The center finished 6th in the league in scoring with 34 goals and 89 points in 72 games to go with 72 penalty minutes and a +23 rating. For his efforts, Fadden was named a Second Team WHL Eastern Conference All-Star and in the playoffs he helped his club reach the WHL finals by scoring 5 goals and 20 points in 19 games with with 19 penalty minutes and a -3 rating. After not receiving an NHL contract in the summer of 2008, Fadden returned to Lethbridge. He started the season slow statistically, with just 5 points in 9 games, and was quickly traded to Tri-City.
Fadden will likely sign with the Lightning this summer and begin his professional career in the organization next season.