There are 7 US Post Offices in Grant County serving a total of 6,422 residents equating to 917 residents per post office. It's estimated that approximately 10,250 packages are handled across the 7 county post offices annually. Grant County is a county located in the U.S. state of Minnesota. As of the 2010 census, the population was 6,018. Its county seat is Elbow Lake. The county was founded in 1868 and named for Ulysses S. Grant, 18th President of the United States. It was later organized in 1874."