U.S. Route 98 is an east–west United States highway that runs from western Mississippi to southern Florida. It was established in 1933 as a route between Pensacola, Florida and Apalachicola, Florida, and has since been extended westward into Mississippi and eastward across the Florida Peninsula. It runs along much of the Gulf Coast between Mobile, Alabama and Crystal River, Florida, including extensive sections closely following the coast between Mobile and St. Marks, Florida.

As of 2005, the highway's western terminus is near Washington, Mississippi, at U.S. Route 61. Its eastern terminus is Palm Beach, Florida, at State Road A1A.