Smith was selected by the Suns with the 16th pick in the 2018 NBA Draft. Through a variety of trades, his rights ended up with the 76ers. Smith appeared in six games for Philadelphia, making two starts. He began the season injured and did not make his debut until Mar. 25. In that debut, he came off the bench against the Orlando Magic and scored three points. Smith's highest scoring output came in the final game of the regular season, when he notched 17 points as part of a 125-109 victory over the Bulls. He also played 11 games for the Delaware Blue Coats of the G League, averaging 7.2 points and 1.6 assists. Smith came off the bench in two playoff games, totaling a little over five minutes and tallying a steal.
June 21, 2018Drafted by the Phoenix Suns in the 1st round (16th pick) of the 2018 NBA Draft and traded along with a 20211st round draft pick to the Philadelphia 76ers in exchange for Mikal Bridges.
July 2, 2018Signed a multi-year rookie contract with the Philadelphia 76ers.