There are 5 US Post Offices in Louisa County serving a total of 9,475 residents equating to 1,895 residents per post office. It's estimated that approximately 15,123 packages are handled across the 5 county post offices annually. Louisa County (loo-WEYE-z\u0259) is a county located in the U.S. state of Iowa. As of the 2010 census, the population was 11,387. The county seat is Wapello. Louisa County is part of the Muscatine Micropolitan Statistical Area."