Sean Allen enters his first season as an assistant coach for the Williams College men's ice hockey program during the 2026-27 season.

Allen arrives on campus after serving as an assistant coach and being active in the recruiting area at SUNY Cortland during the 2025-26 academic year. While with the Red Dragons, Allen was responsible for the third-best team defense in the State University of New York Athletic Conference (SUNYAC). He oversaw special teams, which compiled the third-most, power-play goals in the conference and maintained a penalty-kill success rate consistently around 85%.

During the 2024-25 season, Allen served as an assistant coach and recruiting coordinator at Trine University in Angola, Indiana, focusing on the defense and penalty kill. The program made its first-ever NCAA Tournament appearance, as the team ultimately reached the Elite Eight. During the tremendous run, the Thunder earned a top-five national ranking for the first time in team history, reaching as high as No. 4 in the country. During the first 13 games of the year, the team did not allow a single power-play goal and the unit saw a defenseman be named to the All-Conference First Team.

Allen has also spent time as a consultant for the Nanaimo Clippers in British Columbia since 2022. From 2021-24, he was a part-time assistant coach for the UCLA club hockey team in Los Angeles. He guided the team to the American Collegiate Hockey Association (ACHA) regionals all three years and to the regional finals twice.

Throughout this coaching career, Allen has become proficient in player development, video analysis, game strategy, recruiting, practice planning, team operations, travel coordination, leadership and communication.

In 2021, the outstanding leader earned a bachelor's degree in economics from Hamilton, garnering Dean's List recognition during his undergraduate studies. During his time in Clinton, New York, Allen played on the men's ice hockey team, reaching the NESCAC quarterfinals in 2017-18 and semifinals during the 2018-19 season. He was named a captain prior to the COVID-19-canceled season in 2020-21. Allen worked as a hockey analytics intern for the St. Louis Blues, helping with free agency, arbitration, draft preparation and return-to-play initiatives during the COVID-19 bubble.