2008-09: Ryan Haggerty skated for Trinity Catholic High School in Connecticut and was selected to represent New England in USA Hockey's Select 16 Festival in June.
2009-10: Haggerty moved to Ann Arbor, MI to skate in USA Hockey's National Team Development Program. He skated in two games with the program's U18 team with no points nor penalties. Haggerty scored 5 goals with 6 assists in 34 games for the NTDP's U17 team. Playing for the gold medal USA U17 squad at the 2010 World Hockey Challenge he scored 1 goal with 2 assists. In November he committed to playing college hockey at RPI in 2011-12.
2010-11: Haggerty returned to Ann Arbor to skate for the NTDP's U18 team and was part of the gold medal-winning USA U18 team at the 2011 World Junior Championship. He scored 11 goals with 18 assists and 22 penalty minutes in 54 games for the NTDP U18 squad. Haggerty scored 2 goals and was +3 in six games at the WJC.
2011-12: Haggerty skated in 35 of 39 games in his freshman season at RPI and was the fourth-leading scorer for the Engineers. He scored 7 goals with 8 assists and was -9 with 30 penalty minutes. RPI finished10th in the 12-team ECAC Hockey league. The Engineers upset Clarkson in a first round playoff series before being swept by Union.
2012-13: Haggerty was RPI's fourth-leading scorer in his sophomore season. In 36 games he scored 12 goals with 14 assists and was -6 with 30 penalty minutes. RPI finished second in a competitive ECAC Hockey race but failed to receive an NCAA tournament bid after losing to Brown in a three-game ECAC quarterfinal series.
2013-14: Haggerty had a breakout season for RPI in his junior year and signed a pro contract with the New York Rangers following the season. He led the Engineers with 28 goals and 15 assists in 35 games and was +7 with 42 penalty minutes. RPI finished seventh in ECAC Hockey, ending the year 15-16-6. The Engineers were defeated by Dartmouth in back-to-back games on home ice in the ECAC first round after winning the first game of their series. The Rangers signed Haggerty to an entry-level contract on March 12th, 2014.
The Rangers signed Haggerty to an entry-level contract on March 12th, 2014.