There are 7 US Post Offices in Newaygo County serving a total of 43,605 residents equating to 6,229 residents per post office. It's estimated that approximately 69,598 packages are handled across the 7 county post offices annually. Newaygo County is a county located in the U.S. state of Michigan. As of the 2010 census, the population was 48,460. The county seat is White Cloud. The county was created in 1840 and organized in 1851. It was either named for an Ojibwe leader who signed the Saginaw Treaty of 1819 or for a Native American word meaning \"much water\"."