Across 129 NCAA games, she scored 148 points, finishing in the top-10 all-time scorers for Harvard and being named a top-10 finalist for the 2013 Patty Kazmaier Award.

In October 2013, Dempsey joined the Bisons de Neuilly-sur-Marne on loan for the first round of the 2013–14 IIHF European Women's Champions Cup, where she scored 13 points in 3 games.

[8] On Sunday, January 26, 2020, Jillian Dempsey became the first player in league history to reach 100 career points, including playoffs.

[11] When the playoffs resumed in Boston in March, she was again at full health and captained the Pride to their second Isobel Cup Championship as the only remaining player from the first win in 2016.

[12] On December 12, 2022, Dempsey tied a PHF record with six points on Sunday including her first career hat-trick to lead Boston in a 7-5 win versus Buffalo.

[18][19] She continued teaching while playing in the NWHL, including conducting class from her hotel room during the 2020–21 Lake Placid bubble.