At Michigan, he was a member of the 2017–18 team that won the 2018 Big Ten tournament and advanced to that season's national championship game.

As a freshman at Rufus King High School in Wisconsin, Poole once made a three-point shot to tie a game in the closing seconds after coming off the bench.

[3] Poole visited Illinois, Wisconsin, Indiana, Drake and Marquette as a blue chip high school basketball recruit.

Poole had several competing offers including Illinois, Indiana, Nebraska, Memphis, Marquette, Virginia Tech and Auburn.

[9] On July 1, 2016, Poole announced that he would transfer from Rufus King to La Lumiere School in Indiana for his senior year, where he would experience a campus lifestyle, play a schedule with several ESPN broadcasts, and be teamed up with then-unsigned class of 2017 prospects Brian Bowen and Jeremiah Tilmon.

[10][11] By the time Poole signed his letter of intent to play college basketball for Michigan as part of a three-scholarship player incoming class with Isaiah Livers and Eli Brooks on November 11, 2016, he was the 90th-ranked overall prospect.

[13][14] La Lumiere, which included 2017 McDonald's All-Americans Bowen and Jaren Jackson Jr.,[17] defeated perennial power Montverde Academy, who was led by Canadian sophomore R. J.

[31][32] On March 4, a victory over (#8 AP Poll/#8 Coaches Poll) Purdue gave Michigan its second consecutive Big Ten tournament championship,[33][34][35] even though Poole slumped during the four-game run, missing all nine of his three-point shots.

[53][54] On March 23, Michigan defeated Florida 64–49 in the second round of the 2019 NCAA Division I men's basketball tournament.

[55][56] Following the season, on April 9, 2019, Poole (along with teammates Iggy Brazdeikis and Charles Matthews) declared for the 2019 NBA draft with the intention of hiring agents.

[59] In the Warriors opening game of the 2019–20 season on October 24, Poole made his NBA debut, coming off the bench in a 122–141 loss to the Los Angeles Clippers with five points, two rebounds, two assists and a steal.

[62] In his second game, he made five three pointers in a loss against the Texas Legends, scoring 31 points and posting five rebounds, four assists and three steals.

[67] Poole beat out Otto Porter Jr. and Lee for the 2021–22 Warriors' starting shooting guard spot, while Thompson continued to recover.

The 17-game 20+-point streak ended on April 7, against the Los Angeles Lakers on a night where Poole scored 19 points and set a career-high with 11 assists to contribute to a 128–112 victory.

[79] On April 16, in Game 1 of the first round of the 2022 NBA playoffs, he started and scored 30 points in a 123–107 win over the Denver Nuggets.

[95] On July 6, 2023, the Warriors traded Poole, Patrick Baldwin Jr., Ryan Rollins and draft picks to the Washington Wizards in exchange for Chris Paul.

[100] On January 18, 2025, Poole made his second appearance at the Chase Center, the home court of the Warriors, as a visiting player since the trade.

[102] Although criticized when entering the league for his lack of polish, Poole developed into a dynamic and efficient scorer throughout his tenure with the Warriors.

[103][104] In addition to his shooting ability, Poole is a prolific finisher at the rim, frequently slashing to the basket using his ball-handling skills and speed while being a proficient mid-range shot creator.

[106] His combination of abilities has drawn comparisons to former Warriors teammate Stephen Curry,[107] with some basketball media writers referring to him as the "third Splash Brother".