San Antonio Spurs (2017–2022) White was one of 60 NBA prospects invited to the 2017
NBA draft combine. He was one of only 15 combine invitees who had not been
Rivals top-150 prospects in high school, and one of only three who did not sign with Division I programs out of high school. In addition, according to
Yahoo! Sports writer Jeff Eisenberg, White was also "the only one who will use part of his first NBA contract to pay off student loans he accumulated paying for tuition at UCCS as a freshman." He was later included in the Spurs'
2017 NBA Summer League roster. On July 6, 2017, White signed with the Spurs. On October 18, 2017, White made his NBA debut, coming off the bench in a 107–99 victory over the
Minnesota Timberwolves, yet he recorded no statistics. On October 31, White and
Dāvis Bertāns were sent to the
Austin Spurs of the
NBA G League. White suffered a fractured wrist during a G League game against the
Texas Legends. He was later recalled to San Antonio. On March 12, 2018, White scored a career-high 14 points along with four rebounds, an assist, and a block in a 109–93 loss to the
Houston Rockets. On April 14, 2018, White made his
NBA playoffs debut, coming off the bench with seven points, an assist, a steal, and a block in a 113–92 loss to the
Golden State Warriors in Game 1 of the series. On October 12, 2018, White was revealed to have a left plantar fascia tear. On November 7, he made his season debut, recording a rebound and three assists in a 95–88 loss to the
Miami Heat. On December 31, White scored a career-high 22 points with three rebounds, three assists, two blocks, and a steal in a 120–111 victory over the
Boston Celtics. On January 10, 2019, he scored another career-high 23 points with eight assists, five rebounds, two steals, and a block in a 154–147 double-overtime victory over the
Oklahoma City Thunder. On January 31 against the
Brooklyn Nets, White recorded a then-career-high 26 points as the Spurs won 117–114. On April 18 against the
Denver Nuggets, he recorded a then-playoff career-high of 36 points to give San Antonio a 2–1 lead in the first round of the 2019 playoffs. On December 21, 2020, the Spurs announced that they had signed White to a reported four-year, $73 million rookie-scale extension. On April 1, 2021, against the
Atlanta Hawks, he hit a career-high seven three-pointers and finished the 134–129 double-overtime loss with 29 points, three assists, two blocks, and a rebound.
Boston Celtics (2022–present) 2021–22 season: First NBA Finals appearance On February 10, 2022, White was traded to the
Boston Celtics in exchange for
Josh Richardson,
Romeo Langford, a 2022 first-round pick (which turned into
Blake Wesley), and the rights to swap 2028 first-round picks. He made his Celtics debut the following day against the
Denver Nuggets and finished the 108–102 victory with 15 points, six rebounds, two assists, and a steal. During Game 6 of the
Eastern Conference Finals against the
Miami Heat on May 27, White scored 22 points on 7-for-14 shooting, alongside five assists, three steals, and a block in a 111–103 loss. The Celtics would go on to eliminate the Heat in seven games, earning White his first NBA Finals appearance in his career. In Game 1 of the
NBA Finals on June 2, White had 21 points, three assists, and a rebound during a 120–108 comeback victory over the
Golden State Warriors. The Celtics went on to lose the series in six games despite a 2–1 lead.
2022–23 season: Transition to starter White began the season as a starter for the Celtics. On February 10, 2023, against the
Charlotte Hornets, he scored a career-high 33 points in a 127–116 victory. Three days later, White was named Eastern Conference Player of the Week after averaging 24.5 points, 4.8 rebounds, and 7.5 assists as a starter in place of the injured
Marcus Smart. White started in 70 games and appeared in all 82 regular season games, both career highs. He also shot 38.1 percent from three and 87.5 percent from the free throw line, while registering 76 blocked shots (all career highs). In May, White was named to the
NBA All-Defensive second team for the first time in his career. In Game 6 of the
Eastern Conference Finals on May 27, White had 11 points, six assists, four rebounds, three blocks, and a steal while making a
buzzer-beating put-back shot as time expired to narrowly defeat the
Miami Heat 104–103 to force a Game 7 in Boston, saving the Celtics from elimination. He became the second player in NBA history to hit a buzzer-beating game-winner with his team trailing and facing elimination, joining
Michael Jordan's "
The Shot" in
1989. Two days later, the Celtics went on to lose Game 7 103–84, where White had 18 points, two rebounds, an assist, and a steal.
2023–24 season: First NBA championship White remained a starter after
Marcus Smart was traded to the
Memphis Grizzlies in the offseason. White's production increased as he averaged 15.2 points, 5.2 assists, and 4.2 rebounds per game. White appeared in 73 games (all starts) and shot 46.1 percent from the field, including a career-high 39.6 percent from three. On March 18, 2024, White recorded his first career triple-double with 22 points, 10 rebounds, and 10 assists in a 119–94 victory over the
Detroit Pistons. During Game 4 of the
first round of the playoffs against the
Miami Heat on April 29, 2024, White had a playoff career-high 38 points, four rebounds, three assists, and three blocks in a 102–88 road victory. During Game 4 of the
Eastern Conference Finals against the
Indiana Pacers on May 27, he scored 22 points on 7-for-14 shooting, alongside five steals, four rebounds, four assists, and three blocks while making the game-winning three-pointer as the Celtics completed a 105–102 comeback victory and advanced to the NBA Finals for the second time in three years. White helped the Celtics win the
NBA Finals, where they defeated the
Dallas Mavericks in five games.
2024–25 season: Contract extension On July 1, 2024, a day before his 30th birthday, White signed a four-year, $125.9 million extension with the Celtics. On March 5, 2025, White scored a career-high 41 points in addition to recording three steals, three rebounds, two assists, and a block in a 128–118 victory over the
Portland Trail Blazers as he and
Payton Pritchard became the first Celtics teammates to make nine or more three-pointers in the same game (Pritchard had 10) and the first to score 40 or more points in the same game (Pritchard had 43). They are also the first NBA teammates to score 19 three-pointers in a single game, and the first to have at least 40 points and seven three-pointers each. On March 31 against the
Memphis Grizzlies, White had 14 points, eight rebounds, and 10 assists in the 117–103 victory while setting the Celtics franchise record with the most three-pointers in a season, with 246. He finished the season playing and starting in 76 games, marking the first time White started in every game he played during his career as he averaged 16.4 points, 4.8 assists, and 4.5 rebounds per game. During Game 1 of the
first round of the playoffs against the
Orlando Magic, White led the Celtics in scoring with 30 points while also recording four rebounds, two assists, and two blocks. In Game 5 of the Eastern Conference Semifinals on May 14, he had 34 points, three blocks, three rebounds, and two assists as the Celtics defeated the
New York Knicks 127–102 to force a Game 6 in New York, saving the Celtics from elimination. The Celtics went on to lose the series in six games. On December 30, 2025, White had 27 points, seven rebounds, six assists, and a career-high seven blocks in a 129–119 victory over the
Utah Jazz. His seven blocks tied
George Gervin,
Dennis Johnson,
Doug Christie, and
Tracy McGrady for the most recorded in a game by a guard in NBA history. On March 3, 2026, the NBA announced that White had been named the Eastern Conference Defensive Player of the Month for February. ==National team career==