There are 16 US Post Offices in Kalamazoo County serving a total of 202,719 residents equating to 12,670 residents per post office. It's estimated that approximately 323,562 packages are handled across the 16 county post offices annually. Kalamazoo County is a county located in the U.S. state of Michigan. As of the 2015, the population was 260,263. The county seat is Kalamazoo. Kalamazoo County is included in the Kalamazoo, Portage, MI Metropolitan Statistical Area."