U.S. Route 98 (US 98) is a major east-west thoroughfare through the U.S. state of Florida. Spanning , it connects Pensacola and the Alabama state line to the west with Palm Beach and the Atlantic coast in the east. It is the longest US road (and the longest route of any kind) in Florida, as well as the longest US road in any state east of the Mississippi River.

It was established in 1933 as a route between Pensacola and Apalachicola, 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 Alabama-Florida state line to St. Marks.

Within Florida, US 98 is marked as an east–west road from the Alabama state line to Perry. Throughout most of the Florida Peninsula, the road is marked as a north–south road, but directions return to east–west on the northeast shore of Lake Okeechobee.

As is the case with all Florida roads with federal designations, the entirety of US 98 has a hidden Florida Department of Transportation designation: State Road 80 from the US route's eastern terminus at SR A1A in Palm Beach to Main Street (SR 15) in Belle Glade. State Road 15 from Hooker Highway (SR 812/SR 80) in Belle Glade to the junction with Parrot Avenue (US 441 / SR 15) and Park Street (SR 70 east) in Okeechobee. State Road 700 from the route's eastern split in Canal Point to Lake Parker Avenue (SR 700 north) in Lakeland, and again from to US 92 in Lakeland to South Suncoast Boulevard (US 19) in Citrus County. State Road 35 from SR 60 / Broadway Avenue (SR 35 south) in Bartow to US 301 in Pasco County, with one exception: State Road 548 from Main Street (SR 35 north) to George Jenkins Boulevard (SR 548 west) in Lakeland. State Road 55 from South Suncoast Boulevard (US 19 south) in Citrus County to US 221 (SR 55 north) in Perry. State Road 30 from US 221 in Perry to the Alabama state line via the Lillian Bridge over Perdido Bay, with the following exceptions: State Road 30A between the eastern and western termini of both of US 98 Business (SR 30) and US 98 Alternate (SR 30) in Bay County State Road 289 from US 98 Business (SR 30) to US 90 (SR 10A) in Pensacola. State Road 10A from North 9th Avenue (SR 289 north) to North Pace Boulevard (SR 292 north) in Pensacola. State Road 292 from West Cervantes Street (US 90 / SR 10A) to US 98 Business (SR 30) in Pensacola.

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.

Route description US 98 is a route that extends from the panhandle to Palm Beach. From the Alabama state line to Apalachee Bay, it follows the coast of the Gulf of Mexico through Pensacola and Panama City. It then turns inland and passes through Perry and Chiefland before turning back towards the gulf coast north of Crystal River. The highway stairsteps its way across the peninsula through Dade City, Lakeland, and Sebring. Near Lake Okeechobee, it follows the northern and eastern shore toward Belle Glade. It then heads east to its endpoint on the Atlantic seaboard in Palm Beach.

Across the Panhandle

US 98 enters Florida from Alabama via the Lillian Bridge which spans Perdido Bay. The two-lane highway lands on the state's western shore just west of Pensacola as Lillian Highway. At an intersection with SR 298 and County Road 297 (CR 297), Lillian Highway splits away from US 98 and continues along the state road. At SR 173, US 98 widens into a four-lane divided highway. SR 727 provides access to Warrington to the south and to Pensacola's northwestern suburbs. As it enters West Pensacola, US 98 passes along the southern border of the Corry Station Naval Technical Training Center. It turns north onto SR 295 and the two routes head north together for a short distance. Both SR 173 and SR 295 direct traffic to Naval Air Station Pensacola, which lies south of the intersection of US 98 and SR 295.

US 98 enters Pensacola after traversing a short bridge across Bayou Chico. A few blocks later, it turns onto Pace Boulevard (SR 292), which takes US 98 north to West Cervantes Street, which carries US 90. Together, US 90 and US 98 run through the heart of Pensacola. They intersect US 29 (N. Palafox Street), a half diamond interchange with Interstate 110 (I-10), and the SR 291 one-way couplet of Dr. Martin Luther King Jr. Drive (southbound) and Davis Highway (northbound). Shortly thereafter, US 98 turns south at SR 289 and splits away from US 90. US 98 and SR 289 are concurrent for a few blocks until the U.S. Highway's eastbound traffic turns onto E. Chase Street; westbound traffic arrives at SR 289 on E. Gregory Street. After a short jaunt on the Bayfront Parkway, US 98 turns south to cross the Pensacola Bay Bridge over the eponymous body of water.

The highway lands on the Fairpoint Peninsula in Gulf Breeze. It passes Gulf Breeze High School before it turns to the east. On the opposite end of the eastward curve is a trumpet interchange with Pensacola Beach Boulevard, which heads south to Pensacola Beach. East of Gulf Breeze, US 98 goes through the Naval Live Oaks Reservation. It meets SR 281 in Tiger Point. The route then continues on through Navarre, where it intersects with Florida State Road 87 and then the Navarre Beach Causeway.

US 98 continues on to Perry through Okaloosa, Walton, Bay, Gulf, Franklin, Wakulla, Jefferson, and Taylor counties, passing through different cities and towns, such as Fort Walton Beach, Destin, Miramar Beach, Florida Santa Rosa Beach, Panama City, Port St. Joe, and Apalachicola, along the well-known Emerald Coast and the quieter, less developed Forgotten Coast.

South turn: Concurrency with US 19 Within the city limits of Perry, US 98 and SR 30 makes a sharp turn to the south along US 19 which is also the northern terminus of US 27 Alternate and is named Byron Butler Parkway. US 27, which replaces US 98 as an overlapping US route for US 19 heads east along hidden State Road 20. It also briefly carries US 221 Truck until it reaches County Road 359A (Wright Road). The intersection with US 19/US 27/US 27 Alt./US 221 Truck marks the point where US 98 changes from an east-west to a north-south signed designation, an exception to the conventional numbering scheme for U.S. Highways, under which even-numbered routes are typically signed as east-west routes.

US 221 terminates at US 98 along with that truck route, and the hidden route SR 55 joins the concurrency. In Bucell Junction, State Road 30 turns east State Road 30A near the Perry-Foley Airport. SR 30 turns east as it heads towards US 27 east of the Perry City Limits. and SR 55 becomes the sole secret designation. Later on, US 19-98-ALT 27 enters Tennille, where it intersects with State Road 51. After this the road crosses the Steinhatchee River as it enters Dixie County and begins to make less of a southerly turn and more of an easterly one. The rest of the way, US 98 passes through small towns such as Shamrock where it intersects County Road 358 twice. The road starts making more of an east turn after this and shortly afterwards encounters CR 351 in Cross City, and then State Road 349 and CR 349 in Old Town, which used to be US 129 Alternate. It even contains a Truck Weight station in the median before it follows the left bank of the Suwannee River and intersects the eastern terminus of County Road 55A, before it crosses the Joe H. Anderson Sr. Bridge over the Suwannee River. After this it enters Fanning Springs, where it runs along the border of Gilchrist and Levy Counties. US 19-ALT 27-98 makes a sharp right turn after the intersection of State Road 26 and finally enters Levy County entirely. South of there US 98 continues its pattern of having a limited number of left-turn lanes in the center-median. Recent development in the area may lead to the addition of such turn lanes.

In Chiefland, US 19-98-Alt 27 has a brief hidden concurrency with State Road 320. The hidden route is exposed as SR 320 turns west into Manatee Springs State Park. Later it encounters an intersection with the southern terminus of US 129. Almost instantly, US 27 Alternate leaves US 19-98 onto hidden SR 500 as it heads towards Bronson and Williston. This intersection was transformed into a 90-degree intersection, which directly faces a local high school. From there, US 19-98 runs along an abandoned railroad line along the east side, while the median is widened and lined with the trees that existed before the road was ever built. Blinking signals exist over the intersection with State Road 24 in Otter Creek, and at some point south of there, an overlap with CR 336 begins. At the intersection of County Road 326 in Gulf Hammock, an old locomotive and caboose is on display, and eventually Goethe State Forest where ironically the wide, tree-lined median comes to an end before reaching an at-grade interchange with State Road 121 & County Road 336 in Lebanon Junction. Leaving the forest, the road crosses the Ten Mile Creek bridge. South of Lebanon Junction, US 19-98 runs along sparse residences, trailer parks, a Florida Sheriff's Youth Facility, the Gulf Hammock Wildlife Management Area.

US 19-98 eventually enters the city of Inglis, where it serves as the eastern terminus of CR 40A. A more important intersection is encountered deeper within the city, and that intersection happens to be its parent route County Road 40. West of US 19-98, CR 40 is named "Follow That Dream Boulevard" for the 1962 movie starring Elvis Presley. A small four-lane bridge carries US 19-98 across the Withlacoochee River as it crosses the Citrus-Levy-Citrus County Line. After running between a pair of trailer parks and a sand mine, it approaches a much larger bridge. The Cross Florida Barge Canal was the last section of US 19 that is two lanes wide in Citrus County. A new four-lane divided bridge was completed by FDOT in the early-2010s, which was originally planned in conjunction with the proposed Suncoast Parkway extension to Red Level. Before reaching the potential site of this interchange, it runs by a field where American Civil War re-enactments are staged lies just north of the back entrance to a local quarry, which is across from the western terminus of County Road 488. The quarry obstructs a former segment of US 19-98, as does the territory for the Crystal River Nuclear Power Plant. South of there US 19-98 passes by sparsely located hotels, bars, houses, cluster developments and signs advertising locally prepared peanuts, and in between also passes by the Seven Rivers Regional Medical Center.

As the road approaches a car dealership on the northwest corner of West State Park Drive, a local road leading to Crystal River Preserve State Park one truly begins to feel that he or she has entered the City of Crystal River, since it then passes by the Crystal River Mall, and the divider ends as US 19-98 becomes a four-lane undivided boulevard. It then curves east as it passes by some more motels and restaurants on the water across from City Hall then approaches County Road 495 (North Citrus Avenue). East of this intersection, it crosses the Cross Town Trail, a small rail-trail that was once an Atlantic Coast Line Railroad line spanning from Homosassa through Dunnellon. The road starts to curve south again, just north of the intersection of State Road 44, but it also has a hidden concurrency with SR 44 south of that point. From Northeast First Terrace a divided and some bicycle lanes begin once again.