what county is bay saint louis ms in
Homefacts City Report. Bay St. Louis is located in Hancock County, MS. The population is 9,614, making Bay St. Louis the largest city in Hancock County. There are 4 public schools in Bay St. Louis with an average Homefacts rating of B+. The total crime rate for Bay St. Louis is high, and there are 48 registered sex offenders residing in the city.