Amateur DeAngelo left Washington Township at the age of 14 to play
junior ice hockey for the
Cedar Rapids RoughRiders of the
United States Hockey League (USHL). He was the youngest player in USHL history, often competing with college athletes. DeAngelo played 28 games with the RoughRiders in the
2010–11 USHL season, scoring one
goal and 14
assists for a total of 15
points. In January 2011, he suffered a
broken patella while blocking a
slapshot in a game against the
Des Moines Buccaneers, and the injury kept him out for the rest of the season. After watching his performance in the USHL, the
Sarnia Sting of the
Ontario Hockey League (OHL) selected DeAngelo in the second round, 24th overall, of the 2011 OHL Priority Selection Draft. DeAngelo considered continuing with the USHL, which carried a potential invitation to the
USA Hockey National Team Development Program, but chose to sign with Sarnia because it offered him a faster opportunity to progress his career than waiting to play college hockey. He struggled to adjust to the new league, saying that it took "[m]aybe 15, 20 games before I started getting power-play time and was able to do what I do". As a rookie in the
2011–12 OHL season, DeAngelo scored 23 points in 68 games. He found his stride in the
2012–13 season, improving to 58 points in 62 games, the fifth-highest for Sarnia that season. Beginning in
2013–14, DeAngelo's on-ice behavior began to overshadow his athletic performance. He was removed from the ice during the second period of the Sting's game against the
Guelph Storm on January 31, 2014, and the OHL released a statement on February 14 that DeAngelo would be suspended for eight games following a violation of the league's Harassment and Abuse/Diversity Policy. The OHL statement also revealed that this was DeAngelo's second suspension that season for violating the Abuse/Diversity policy, but that this was the first time his comments were directed towards a teammate. The details of his first suspension were kept confidential. Later in the season, DeAngelo received a two-game suspension for abuse of an official. He returned on March 14 for the final game of the season, against the
Erie Otters, but was ejected in the third period for another abuse of an official violation. Going into the 2014
National Hockey League draft, DeAngelo was considered a top North American prospect. He led all OHL defensemen in scoring with 71 season points (15 goals and 56 assists), and was ranked No. 10 in the
NHL Central Scouting Bureau's 2014 midterm report. He also made an appearance for Team Cherry at the 2014
CHL/NHL Top Prospects Game. On June 27, 2014, the
Tampa Bay Lightning selected DeAngelo in the first round, 19th overall, at the
2014 NHL entry draft. Lightning director of amateur scouting Al Murray addressed DeAngelo's past suspensions, saying he believed that some of the incidents were "blown out of proportion", while general manager
Steve Yzerman said that the organization believed "he'll change and grow up". He signed a three-year,
entry-level contract with the team on December 2, 2014. On January 7, 2015, the Sting traded DeAngelo to the
Sault Ste. Marie Greyhounds in exchange for Anthony Salinitri and three future draft picks. At the time, he had 38 points in 29 season games with the Sting. At the end of the season, DeAngelo was awarded the
Max Kaminsky Trophy, given to the OHL's Most Outstanding Defenseman of the Year. He led all defensemen for scoring that season, with 89 points in 55 games, including 25 multi-point games. He was the fourth Greyhound in OHL history to receive the award. He was also named the
CHL Defenceman of the Year for the 2014–15 season.
Professional Tampa Bay Lightning After attending training camp in 2015, DeAngelo was assigned to the Lightning's 2015
American Hockey League (AHL) affiliate, the
Syracuse Crunch. After accruing no
penalty minutes in his first 19 AHL games, he was given two 10-minute game misconduct penalties in a December 7 match against the
Albany Devils, first for conduct against
Joseph Blandisi, and then for commentary against a referee. While he had an offensively-productive season with the Crunch, scoring six goals and 37 assists in 69 games, DeAngelo was also a
healthy scratch for eight games, a decision rumored to be a combination of behavioral issues and poor defensive ability.
Arizona Coyotes On June 25, 2016, in the midst of the
2016 NHL entry draft, the Lightning traded DeAngelo to the
Arizona Coyotes in exchange for the No. 37 overall draft pick, with which they selected defenseman
Libor Hájek. After being recalled from the
Tucson Roadrunners to replace an injured
Michael Stone, DeAngelo scored his first NHL goal in his professional debut on November 8, 2016, scoring on
Colorado Avalanche goalie
Calvin Pickard in the second period of a 4–2 win. His first NHL assist came later that week, assisting
Radim Vrbata in a 2–1 loss to the
Boston Bruins. On January 1, 2017, DeAngelo was suspended for three games for physical assault of a referee during a 4–2 loss to the
Calgary Flames the day before. The incident occurred towards the end of the second period, when DeAngelo was being steered away from a scrum and shoved away the official's hands. In addition to the suspension, he was required to forfeit $14,388.90 to the Players' Emergency Assistance Fund. DeAngelo finished his first NHL season with five goals and nine assists in 39 games.
New York Rangers On June 23, 2017, the Coyotes traded DeAngelo, as well as the seventh overall pick in the
2017 NHL entry draft, to the
New York Rangers in exchange for
center Derek Stepan and
goaltender Antti Raanta. After
Kevin Shattenkirk suffered a knee injury in January 2018, DeAngelo was called back up to take his place. DeAngelo suffered a sprained ankle during a match against the
Carolina Hurricanes on March 12, and missed the final weeks of the season to recover.
Ryan Sproul was called up to replace him, and he finished the season with eight assists in 32 NHL games. DeAngelo credited his development to the guidance of first-year coach
David Quinn, telling reporters that, "it's been nice to have a coach that communicates more". Quinn had a notable intolerance for the outbursts that had characterized the earlier part of DeAngelo's career; the player was a healthy scratch for about 20 games during the season. DeAngelo was also part of a high-profile incident in which he knocked
Kyle Okposo of the
Buffalo Sabres unconscious in the third period of a 6–2 Rangers victory. Okposo was later diagnosed with his third concussion in as many years. After the 2018–19 season, DeAngelo became a
restricted free agent. Salary negotiations dragged into the Rangers' training camp before DeAngelo agreed to a one-year, $925,000 deal on September 20, 2019, less than two weeks before the start of the season. DeAngelo's stock continued to rise during the
2019–20 season. He scored 53 points, 15 goals and 38 assists, in 68 regular season games, the fourth among all NHL defensemen, before the season was shut down due to the
COVID-19 pandemic. DeAngelo told reporters that "I struggled a little bit early on – maybe the first five, six games I wasn't happy with where my game was – and then from there I kind of picked it up and started to feel real confident." His best game came on January 9, 2020, when DeAngelo scored a
hat trick in a 6–3 win over the
New Jersey Devils. He was the first Rangers defenseman to do so since
Reijo Ruotsalainen in 1982. On October 15, 2020, the Rangers signed DeAngelo to a two-year, $9.6 million contract extension. On opening night of the
2020–21 season, DeAngelo took an unsportsmanlike conduct penalty that Quinn called "undisciplined", and he was subsequently benched for the second game of the season.
General manager Jeff Gorton later said that DeAngelo "wasn't able to move on from that" incident, and that he was told that, if there was another behavioral incident, he would be placed on
waivers. On January 31, 2021, following reports that DeAngelo had a physical altercation with Rangers
goaltender Alexandar Georgiev following a 5–4 overtime loss to the
Pittsburgh Penguins, the Rangers placed DeAngelo on waivers. He cleared the process and was officially assigned to the team's
taxi squad, but Gorton clarified that the assignment was a formality, and that DeAngelo would be kept away from his teammates and other taxi squad skaters. In a press conference after the altercation, Gorton told reporters that DeAngelo had "played his last game for the Rangers". In only six games that season, DeAngelo had one assist and a −6
plus–minus rating. On July 23, 2021, the Rangers placed DeAngelo on unconditional waivers, allowing the team to buy out the remainder of his contract and releasing him as a free agent.
Carolina Hurricanes On July 28, 2021, the
Carolina Hurricanes signed DeAngelo to a one-year, $1 million contract. The signing was controversial among Hurricanes fans, who were aware of DeAngelo's reputation and lamenting the off-season departure of defenseman
Dougie Hamilton, but after recording eight points in the first seven games of the season, DeAngelo was subject to cheers at
PNC Arena. On October 30, DeAngelo registered his first
Gordie Howe hat trick with a goal, an assist, and a fight with
Reese Johnson of the
Chicago Blackhawks.
Philadelphia Flyers On July 8, 2022, the Hurricanes traded DeAngelo to the
Philadelphia Flyers in exchange for a fourth-round selection in the
2022 NHL entry draft, a third-round pick in the 2023 draft, and a second-round pick in the 2024 draft. He agreed to terms on the same day, signing a two-year, $10 million contract with the Flyers. On March 8, 2023, the NHL Department of Player Safety issued DeAngelo a two-game suspension for spearing Tampa Bay Lightning forward
Corey Perry. After rumors that he would be traded back to Carolina, DeAngelo was placed on waivers for the purpose of a buyout on July 14. This made him the first player in NHL history to be bought out more than once, though he would later be joined by
Ryan Suter in 2024.
Second stint with Carolina Following his buyout, DeAngelo signed a one-year deal to return to the Hurricanes on July 24, 2023.
SKA Saint Petersburg On September 23, 2024, DeAngelo signed a one-year contract with
SKA Saint Petersburg of the
Kontinental Hockey League (KHL). In the
2024–25 season, DeAngelo added an instant offensive punch from the blueline and was selected to play in the
KHL All-Star Game. On January 14, after three consecutive losses, and two games after being benched for the third period by coach
Roman Rotenberg for what the coach described as a "hockey situation", DeAngelo and SKA mutually agreed to terminate his contract, officially for family reasons. He ended his tenure with SKA having recorded 6 goals and 32 points through 34 regular season appearances.
New York Islanders On January 24, 2025, having returned to North America as a free agent, DeAngelo was signed to a one-year, league-minimum contract with the
New York Islanders for the remainder of the
2024–25 NHL season. On July 1st, 2025, the Islanders signed DeAngelo to another one-year contract for the 2025-2026 season. ==International play==