Ruiru's 2026 population is now estimated at 505,324. In 1950, the population of Ruiru was 676. Ruiru has grown by 20,622 in the last year, which represents a 4.25% 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 Ruiru, which typically includes Ruiru's population in addition to adjacent suburban areas.