Fort Walton Beach is a city in southern Okaloosa County, Florida, United States. As of 2010, the population estimate for Fort Walton Beach was 19,507 recorded by the U.S. Census Bureau. It is a principal city of the Fort Walton BeachCrestviewDestinMetropolitan Statistical Area. Fort Walton Beach is a year-round fishing and beach resort community. Its busiest time of the year is the summer, with spring break being another busy time when thousands of people flock to the Emerald Coast.