Rentals in Walton County, Florida, United States. Walton County is located on the Emerald Coast in the northwestern part of the U.S. state of Florida, with its southern border on the Gulf of Mexico. As of the 2010 census, the population was 55,043. Its county seat is DeFuniak Springs. The county is home to the highest natural point in Florida: Britton Hill, at 345 feet (105 m).