Clyst St Mary is a small village and civil parish 3 miles (4.8 km) east of Exeter on the main roads to Exmouth and Sidmouth in East Devon. The name comes from the Celtic word clyst meaning 'clear stream'. The village is a major part of the electoral ward of Clyst Valley. At the 2011 Census this ward population was 2,326. At the 2021 census, its population increased to 2,400, which was 3.2% more than that recorded at the 2011 census.