U.S. Route 98 (US 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 eastward across the Florida Peninsula and westward into Mississippi. It runs along much of the Gulf Coast between Mobile, Alabama and Crystal River, Florida, including extensive sections closely following the coast eastward from the Florida-Alabama state line to St. Marks, Florida.

Within Florida, US 98 is marked as an east–west road from the Alabama-Florida border to Perry. Throughout most of the state, the road is marked as a north–south road.

Concurrencies include US 90 in Pensacola, US 319 from Port St. Joe to St. Teresa and in Medart, ALT US 27 from Perry to Chiefland, US 19 from Perry to Chassahowitzka, US 41 then SR 50A in Brooksville, SR 50 from Brooksville to Ridge Manor, US 301 from Moss Town to Clinton Heights, US 17 from Bartow to Fort Meade, US 27 from West Frostproof to South Sebring, US 441 from Okeechobee to Royal Palm Beach and SR 80 from near Belle Glade to Palm Beach.

The hidden designation for most of US 98 across the panhandle of the state of Florida is State Road 30. Between Perry and Chassahowitzka the hidden designation is State Road 55. Between Chassahowitzka and Palm Beach, the hidden designation is State Road 700.

Mar-A-Lago is next to the southern terminus of US 98 at A1A, in Palm Beach.