There are 33 US Post Offices in Weld County serving a total of 238,539 residents equating to 7,228 residents per post office. It's estimated that approximately 380,735 packages are handled across the 33 county post offices annually. Weld County is one of the 64 counties of the U.S. state of Colorado. As of the 2010 census, the population was 252,825. The county seat is Greeley. Weld County comprises the Greeley, CO Metropolitan Statistical Area, which is also included in the Denver-Aurora, CO Combined Statistical Area.