Professional
Bouchard was selected in the first round, 10th overall by the Edmonton Oilers in the 2018 NHL entry draft. A few weeks later on July 17, 2018, the Oilers signed Bouchard to a three-year, entry-level contract. On October 25, Bouchard became the youngest Oilers defenceman in history to record a goal when he scored in a 4–1 win over the Washington Capitals. He had turned 19 five days before the game. After seven games with the Oilers, he was returned to the Knights on November 2. Despite only skating in 45 games for the Knights during the 2018–19 season, Bouchard recorded 16 goals and 53 points. He added another 21 points in 11 games during the OHL postseason. On April 25, 2019, Bouchard was named the winner of the Max Kaminsky Trophy as the league's top defenceman.
Due to the COVID-19 pandemic's effect on the American Hockey League (AHL), he spent part of the 2020–21 season with Södertälje SK of Sweden's HockeyAllsvenskan. He then joined the Oilers for the shortened regular season, though it was noted that he had some difficulty getting ice time despite solid play.
In the 2021–22 season, Bouchard solidified his place in the roster, managing 12 goals and 31 assists in 81 regular season games, pairing alongside future Hall of Famer Duncan Keith, while also leading the team's second power play unit. 35 of his points came at even strength play, ranked 14th among NHL defencemen. The Oilers qualified for the 2022 Stanley Cup playoffs, making a deep run to the Western Conference final before losing to the Colorado Avalanche.
On August 24, 2023, Bouchard signed a two-year, $7.8 million contract extension with an AAV of $3.9 million. Bouchard's offensive production doubled in the 2023–24 season, registering career highs in scoring with 18 goals and 64 assists for a total of 82 points, finishing fourth in the league among defencemen. He set a league record in the 2024 Stanley Cup playoffs for assists in one playoff year by a defenceman with 26, surpassing Paul Coffey, who himself obtained the record in 1985 as a member of the Oilers.
On June 30, 2025, Bouchard signed a four-year, $42 million contract extension with an AAV of $10.5 million. On January 24, 2026, his 400th game, Bouchard scored his first NHL hat-trick against the Washington Capitals in a 6–5 overtime win, becoming the first Oilers' defender to score three since Marc-André Bergeron, just over 20 years prior. He factored in on all six goals, setting a career high in goals and points in a single game, as well as becoming the first Oilers' defenceman to have a six-point game since Paul Coffey did so on March 14, 1986. He also joined Bobby Orr as the only defenceman in league history to have six points and eight shots in a single game. On March 26, Bouchard scored the overtime winner against the Vegas Golden Knights, marking his 20th goal of the season. The goal made him the fourth Oilers' defenceman to reach 20 goals in a season, with the others being Coffey, Charlie Huddy, and Sheldon Souray. On April 8, Bouchard registered his 90th point of the season, joining Coffey as the second Oilers' defenceman to reach 90 points in a season. Bouchard would lead all defencemen in points at the end of the season, with 95. The Oilers would end up losing to the Anaheim Ducks in six games in the first round of the 2026 Stanley Cup playoffs. Despite his efforts, Bouchard was not a finalist for the James Norris Memorial Trophy, awarded annually to the defenceman voted the best at his position by the Professional Hockey Writers' Association. He finished the year fourth in Norris voting, making the second NHL All-Star team.
On September 17, 2026, Bouchard was named alternate captain for the Oilers, replacing Darnell Nurse. Bouchard started the 2026–27 campaign by scoring his second career hat-trick and adding two assists in a 6–5 overtime loss to the Vancouver Canucks on September 29, becoming the first Oilers defenceman to open the season with a multi-goal game, the first defenceman since Mark Howe in 1980–81 to open a season with a hat-trick, and the first defenceman in league history to record five points in a season opener. Just two days later, Bouchard had a goal and two assists in a 9–7 win over the Canucks to get his eighth point of the season, breaking Harry Cameron's record for the most points in the first two games of a season by a defenceman set over 100 years prior. The same performance also saw him break Wayne Gretzky's record for the most points in the first two games of a season by an Edmonton Oiler.
Canada
