There are 32 US Post Offices in Delaware County serving a total of 43,717 residents equating to 1,366 residents per post office. It's estimated that approximately 69,777 packages are handled across the 32 county post offices annually. Delaware County is a county located in the US state of New York. As of 2010 the population was 47,980. The county seat is Delhi. The county is named after the Delaware River, which was named in honor of Thomas West, 3rd Baron De La Warr, appointed governor of Virginia in 1609."