On February 8, 2011, with two points in the game against Boston University in the first round of the 2011 Beanpot Tournament, Kelli Stack accumulated 199 points in her career and broke BC's all-time career points record, becoming the new program leader. The previous record had been held by Erin Magee. On January 31, 2011, Kelli Stack became the all-time leading goal scorer in Hockey East Conference history to bring her career total to 65, breaking Jen Hitchcock's record of 61 goals. At the conclusion of her career at Boston College, Stack was voted the New England Division I Player of the Year after leading Hockey East in points and goals. The Second Team All-American scored two goals to help advance the Eagles to the Frozen Four for the second time in her tenure. The three-time Hockey East Player of the Year accumulated 58 points for the season and concluded her collegiate career as BC's all-time leading scorer with 209 points. Stack was among the three finalists nominated for the 2011 Patty Kazmaier Award and the first nominee from Boston College. An award of the USA Hockey Foundation, the Patty Kazmaier Memorial Award is annually bestowed upon the top player in NCAA Division Iwomen's ice hockey. Stack was also nominated for the award in 2009. Stack was also a four-time All-Conference selection, the first player to accomplish this feat in the nine-year history of Hockey East.
USA Hockey
Stack played in all five games contested by the Team USA in the 2010 Winter Olympics. She accumulated eight points, five assists and three goals, with four points in the game against Russia. Team USA went on to win a silver medal, losing to Canada in the gold medal game 0–2. In the second game of the 2011 IIHF Eight Nations Tournament, Stack was one of two US players to register a hat trick in a victory over Japan. In the first game of the 2012 IIHF Women's World Championship, she had three assists in a 9–2 victory over Canada. In a game versus Finland at the 2012 Worlds, she scored a hat trick and added three assists in an 11–0 victory. Stack again played in all five of USA's games at the 2014 Winter Olympics, scoring five points. Team USA won the silver medal, losing to Canada 3–2 in overtime in the gold medal game.
CWHL: Boston Blades
Selected by the Boston Blades in the 2011 CWHL Draft, Stack set a franchise record for most points scored in one season with 42. In round-robin play at the 2012 Clarkson Cup, Stack scored two goals, as the Blades earned a 5–2 victory over the Toronto Furies. During the 2012–13 CWHL season, Stack only played in eight games before suffering a season-ending injury. Despite her injury, she traveled with the Blades to the 2013 Clarkson Cup.
On September 24, 2015, it was announced that Stack had signed with the Connecticut Whale of the professional National Women's Hockey League for the league's inaugural season. In 2016–17, Stack set the franchise record in goals scored with 12 in 16 games played.
The CWHL expanded to have two new teams in Shenzhen as China prepares to host the 2022 Winter Olympics. After being cut from the 2018 USA Olympic team, Stack joined the Kunlun Red Star WIH as a hockey ambassador. Stack earned an assist on the first goal in Red Star WIH history, scored by Zoe Hickel. Stack led the CWHL in points with 49 in 28 games for Red Star WIH. She appeared with the Red Star in the 2018 Clarkson Cup final where she scored the team's only goal of the game in the second period in a 2–1 loss to the Markham Thunder.
