Tacna's 2026 population is now estimated at 352,360. In 1950, the population of Tacna was 17,059. Tacna has grown by 4,866 in the last year, which represents a 1.4% 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 Tacna, which typically includes Tacna's population in addition to adjacent suburban areas.