There are 5 US Post Offices in Valencia County serving a total of 70,901 residents equating to 14,180 residents per post office. It's estimated that approximately 113,166 packages are handled across the 5 county post offices annually. Valencia County is a county located in the U.S. state of New Mexico. As of the 2010 census, the population was 76,569. The county seat is Los Lunas. Valencia County is included in the Albuquerque, NM Metropolitan Statistical Area."