La Union's 2026 population is now estimated at 34,824. In 2007, the population of La Union was 34,045. La Union has grown by 3 in the last year, which represents a 0.01% annual change. These population values and projections come from DIGESTYC Censo de Poblacion y Vivienda 2007 poblacion por municipio and ONEC-DIGESTYC proyecciones municipales de poblacion 2020-2030 revision 2021 .