Thomas Chabot (/ʃəˈbɒt/ shə-BOT; born January 30, 1997) is a Canadian professional ice hockey player who is a defenceman and alternate captain for the Ottawa Senators of the National Hockey League (NHL). Chabot was drafted in the first round (18th overall) by the Senators in the 2015 NHL entry draft. He won a silver medal at the World Junior Championships in January 2017, becoming the first defenceman to be named the most valuable player in the history of the tournament. He also won two silver medals at the IIHF World Championships in 2019 and 2022.

Chabot was born in Sainte-Marie-de-Beauce to Francois, an elementary-school teacher and Claude, a hairdresser. His older brother Felix-Antoine, scored two goals in his only QMHL game. Chabot began skating at three years old. He played in the 2009 and 2010 Quebec International Pee-Wee Hockey Tournaments with his minor ice hockey team from the Beauce-Nord area.

Chabot was selected by the Saint John Sea Dogs of the Quebec Major Junior Hockey League (QMJHL) in the second round, 22nd overall, of the 2013 QMJHL entry draft. In his rookie season in 2013–14, he appeared in 55 games with the Sea Dogs, scoring one goal and 21 assists for 22 points. The following season his outstanding play was rewarded when he was selected to play in the 2015 CHL/NHL Top Prospects Game. He led the team's defence in scoring with 12 goals and 41 points in 66 games, and finished fifth overall on the team. The Sea Dogs qualified for the playoffs but were eliminated by the Baie-Comeau Drakkar in the opening round. He tallied just one assist in the five-game series.

In his third season with the Sea Dogs in 2015–16, Chabot recorded 11 goals and 45 points in 47 games. The Sea Dogs made the playoffs for the second consecutive season and advanced to the semifinals where they were beaten by the Shawinigan Cataractes. In 17 playoff games, he added three goals and 21 points. In 2016–17, his final season with the Sea Dogs, Chabot tallied ten goals and 45 points in 34 games. In February 2017, he was suspended twice by the QMJHL, once for an illegal use of his hockey stick on an opposing player and the second for an illegal check to the head of an opponent. In total he was suspended for four games. On March 15, Chabot set a franchise record as the Sea Dogs' all-time top scoring defenceman. The Sea Dogs qualified for the playoffs for the third consecutive season and defeated the Blainville-Boisbriand Armada to win the President's Cup as champions of the league. In 18 playoff games, he added five goals and 23 points. He was named the playoff most valuable players and awarded the Guy Lafleur Trophy. As league champions, the Sea Dogs represented the QMJHL at the 2017 Memorial Cup, a round-robin tournament in which the champions of the three leagues that comprise the Canadian Hockey League face off against each other and a host team. The Sea Dogs went on to lose in the semifinals to the Ontario Hockey League's Erie Otters. At the conclusion of the season, Chabot earned the Sea Dogs' Top Defenceman Award and the Fans Choice Award. He was also awarded the Emile Bouchard Trophy as the QMJHL's best defenceman and the Paul Dumont Trophy as the league's personality of the year in April. In 2023, he was named to the Sea Dogs Hall of Fame.

Chabot was selected by the Ottawa Senators of the National Hockey League (NHL) in the first round, 18th overall, in the 2015 NHL entry draft. He attended the Senators' 2015 rookie and main training camps after taking part in Hockey Canada's National Team Summer Showcase held in Calgary during late-summer, playing in three preseason games with Ottawa. He was returned to Saint John on September 30, 2015, the same day he signed a three-year entry-level contract with Ottawa. A year later, Chabot attended the Senators' 2016 training camp and made the team, making his NHL debut on October 18, 2016, versus the Arizona Coyotes. Despite remaining with the team for nearly a month, he was a healthy scratch eight times. He was returned to the Sea Dogs in November for his final major junior season after playing in the one game with the Senators.

To start the 2017–18 season, Chabot was sent to Ottawa's American Hockey League affiliate, the Belleville Senators, where he recorded two goals and five assists in 12 games before being recalled by Ottawa in November. He scored his first NHL goal, and recorded two assists, in a 6–5 win over the New York Islanders on December 1, 2017. On April 2, 2018, he recorded two goals and assisted on another in a 6–5 loss to the Winnipeg Jets to record his first multi-goal game. In his first NHL season, he finished with nine goals and 16 assists for 25 points in 63 games, while averaging less than 18 minutes of ice-time per game. Chabot had a breakout season in 2018–19, finishing with 14 goals and 55 points in 70 games, the tenth-highest among NHL defencemen.. He recorded another multi-goal game on October 6, scoring twice and assisting on another in a 5–3 victory over the Toronto Maple Leafs. One month later on November 6, he tallied three points, scoring once and assisting twice in a 7–3 win over the New Jersey Devils. As the season progressed, his ice-time jumped to an average of 25 minutes per game and he assumed first-pairing duties alongside Dylan DeMelo. He was one of only three defencemen under the age of 25 to score 50 points or more, along with Jacob Trouba and Morgan Rielly. However, in November, he was among seven players forced to release an apology after a video was released showing the players discussing the team negatively. That season, Chabot was selected to appear in the NHL All-Star Game. With Ottawa's top two scorers, Mark Stone and Matt Duchene, both sent away at the trading deadline, Chabot finished the season as the team's leading scorer. Following the season, hockey writers began listing Chabot as one of the NHL's top defencemen, The Senators were eliminated from playoff contention in March. In September 2019, he signed an eight-year, $64 million contract extension with the Senators.

To begin the 2019–20 season, Chabot was paired with Nikita Zaitsev, but by November, was back alongside DeMelo. In February 2020, DeMelo was traded away, a deal that was viewed negatively by critics who believed he allowed Chabot to play better when paired with him. Shortly thereafter, the season was suspended on March 12, due to the COVID-19 pandemic. In 71 games, he scored six goals and 39 points as the Senators failed to qualify for the playoffs again. In the pandemic-shortened 2020–21 season he was named as one of the Senators' alternate captains. He made 49 appearances, scoring six goals and 31 points, again anchoring the Senators defence. The Senators were eliminated from the playoffs and on May 4, 2021, Chabot took a hard hit from Jets' defenceman Logan Stanley that forced him to miss the rest of the season.

In the seasons that followed, Chabot was the keystone player in Ottawa's defence corps, which was otherwise considered thin by many commentators and had no stable partner since DeMelo. As a result, he logged very high minutes per game. In the 2021–22 season he averaged 26:23 minutes of ice time per game, the highest for any player on any team in the league. On March 5, 2022. in an 8–5 loss to the Coyotes, Chabot recorded three assists. He repeated the feat on April 29, in a 4–2 victory over the Philadelphia Flyers. He finished with seven goals and 38 points in 59 games. During the 2022–23 season, Chabot struggled, with growing criticism of his game, though some argued that injury and overuse have affected his play. On January 18, 2023, he recorded three assists in a 5–4 overtime victory over the Pittsburgh Penguins. Later that month on January 31, he again tallied three assists, in a 5–4 victory over the Montreal Canadiens. On February 27, he recorded another three-point game, scoring once and adding two assists in a 6–2 victory over the Detroit Red Wings. Chabot missed time with injury again that season, suffering a concussion in November, and an upper body injury in March that ended his season prematurely. In 68 appearances, he tallied 11 goals and 41 points. The Senators did not qualify for the playoffs for the sixth consecutive season.