Rennes's 2021 population is now estimated at 357,874. In 1950, the population of Rennes was 123,363. Rennes has grown by 3,977 since 2015, which represents a 1.12% annual change. These population estimates and projections come from the latest revision of the UN World Urbanization Prospects. These estimates represent the Urban agglomeration of Rennes, which typically includes Rennes's population in addition to adjacent suburban areas.