Frankfort is the capital of the U.S. state of Kentucky and the seat of Franklin County. It is a home rule-class city. The population was 28,6…Frankfort is the capital of the U.S. state of Kentucky and the seat of Franklin County. It is a home rule-class city. The population was 28,602 at the 2020 United States census. Located along the Kentucky River, Frankfort is the principal city of the Frankfort, Kentucky Micropolitan Statistical Area, which includes all of Franklin and Anderson counties.