Bilbao's 2025 population is now estimated at 346,746. In 1950, the population of Bilbao was 227,488. Bilbao experienced a decrease of -1 residents over the past year, marking an annual decline of 0%.These population estimates and projections come from the latest revision of the UN World Urbanization Prospects. These estimates represent the Urban agglomeration of Bilbao, which typically includes Bilbao's population in addition to adjacent suburban areas.