Sacramento Kings (2017–2019) Mason was drafted by the
Sacramento Kings with the 34th pick in the
2017 NBA draft. He played in the
NBA Summer League for the Kings, where he scored 24 points in 24 minutes against the
Los Angeles Lakers on July 10, 2017, adding 6 assists, 5 rebounds and 2 steals. For the full
2017–18 regular NBA season, Mason averaged 7.9 points, 2.5 rebounds and 2.8 assists in 52 games. Mason was waived by the Kings on July 4, 2019.
Milwaukee Bucks (2019–2020) Mason signed a
two-way contract with the
Milwaukee Bucks on July 26, 2019. In the deal, he split time between the Bucks and their
NBA G League affiliate, the
Wisconsin Herd. In the G League, he scored 44 points in a win over the
Grand Rapids Drive on February 19, 2020. Mason was awarded the NBA G League MVP for the 2019–20 season on June 25, 2020. He averaged 26.4 points, 5.0 assists and 3.4 rebounds per game with the Herd.
Orlando Magic (2021) On December 18, 2020, Mason signed with the
Philadelphia 76ers, but was waived the next day and signed with their
NBA G League affiliate, the
Delaware Blue Coats. However, on February 3, 2021, the
Orlando Magic signed him to a
two-way contract right before the beginning of the G League season. However, Mason was waived on February 15 after playing in four games. Two days later, he was re-acquired by Delaware, but was waived on March 5 after suffering a season-ending injury. He didn't log any minutes with the Blue Coats.
South Bay Lakers (2021–2022) Mason joined the
Philadelphia 76ers for the
2021 NBA Summer League. On October 13, 2021, Mason signed with the
Los Angeles Lakers and was waived the following day. On October 23, he signed with the
South Bay Lakers as an affiliate player. In seven games, he averaged 9.1 points, 3.0 rebounds and 3.3 assists per game.
Wisconsin Herd (2022) On February 24, 2022, Mason was traded, along with a 2022 first-round pick, to the
Wisconsin Herd in exchange for
Tremont Waters and a 2022 second-round pick.
SLUC Nancy (2023–2024) On January 15, 2023, Mason signed with
SLUC Nancy Basket of the
LNB Pro A. On June 22, 2024, Mason signed with
Scafati Basket of the
Lega Basket Serie A (LBA). In September 2024, he left the team.
Fujian Sturgeons (2024) On October 5, 2024, Mason signed with
Fujian Sturgeons of the
Chinese Basketball Association (CBA).
Leones de Ponce (2025) On February 14, 2025, Mason signed with
Leones de Ponce of the
Baloncesto Superior Nacional (BSN).
Limoges CSP (2025–present) On August 10, 2025, he signed with
Limoges CSP of the
LNB Pro A. ==National team career==