Hamish Stewart (born 30 July 1999) is a Scottish tennis player. He has a career-high singles ranking of world No. 336 achieved on 8 December 2025 and a career-high doubles ranking of No. 246 achieved on 1 December 2025.
He is from Strathblane in Scotland and later trained in Stirling, Scotland. He played junior tennis at the Wimbledon Championships when he was a teenager in 2017, and won the gold medal at the 2017 Commonwealth Youth Games in The Bahamas for Team Scotland.
He played college tennis in the United States, completing an undergraduate degree at Tulane University and completing a post-graduate course at the University of Georgia in 2022.
He was the Tennis Scotland Open Tour Finals men's champion in 2023, before playing a first full season on the professional tour in 2024, finishing the season ranked fifth in Scotland.
He won a number of ITF World Tennis Tour titles in 2025, including wins in Bucharest, Sunderland and Poitiers, before claiming his fifth and sixth titles of the year in back-to-back events in Egypt in April 2025.
In June 2025, he was won a wildcard into gentleman's singles qualifying event at the 2025 Wimbledon Championships having come through the wild card qualifying play-off, including a win over experienced pro Liam Broady. In the first round of qualifying, he saved a match point before he was awarded a victory after his opponent Valentin Vacherot retired with injury. In the second round he defeated Frenchman Luca Van Assche in three sets before losing in the final qualifying round to Leandro Riedi.
He was a semi-finalist on the ATP Challenger Tour event in Nottingham in July 2025, where he was defeated by compatriot Kyle Edmund in the semi-finals. Playing alongside Harry Wendelken, he reached the final of the men's doubles at the 2025 Open de Vendée in France on the ATP Challenger Tour in October 2025.