Coghlan spent the 2012–13 season with the
Nanaimo Clippers of the
British Columbia Hockey League, where he gained attention from WHL scouts. After he recorded 18 goals and 40 points through 34 games, he was drafted in the third round, 63rd overall, by the
Tri-City Americans in the 2013 Bantam Draft.
Professional Coghlan was signed by the
Vegas Golden Knights as an undrafted free agent after attending the team's inaugural development and NHL training camp on September 20, 2017. On March 10, 2021, Coghlan scored his first career NHL goal and his first career NHL hat trick against the
Minnesota Wild, becoming the third defenceman in NHL history to score his first three career goals in the same game. Additionally, he became the first rookie and the first defenceman to register a hat trick as a Golden Knight in franchise history. On July 13, 2022, Coghlan and
Max Pacioretty were traded to the
Carolina Hurricanes for future considerations. After two seasons with Carolina, Coghlan was traded to the
Winnipeg Jets in exchange for future considerations on July 6, 2024. Following his lone season in the Jets organization, Coghlan re-joined the Golden Knights, signing a one-year contract on July 1, 2025. After being recalled from the AHL on January 8, 2026, Coghlan played his first game for Vegas in nearly four years on the same day, recording just under 16 minutes in a 5–3 victory over the
Columbus Blue Jackets. ==Career statistics==