Hillah's 2026 population is now estimated at 690,911. In 1950, the population of Hillah was 40,712. Hillah has grown by 17,808 in the last year, which represents a 2.65% 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 Hillah, which typically includes Hillah's population in addition to adjacent suburban areas.