Fort Lauderdale-Hollywood International Airport is quietly becoming a much bigger deal for Allegiant Air. The ultra-low-cost carrier is rolling out 11 new nonstop routes from the airport between February 2026 and February 2027, and the expansion has already pushed FLL up the ranks to become the airline's fourth-busiest Florida base and sixth overall.

Five of the new routes launched in February: Albany, Chattanooga, Chicago Rockford, Rochester and Trenton. The Chattanooga route is a direct result of Spirit Airlines pulling out of the market (Spirit has since ceased flying altogether), and Allegiant has clearly spotted a pattern — most of the next wave of routes exists for the same reason.

That next wave arrives in October, when four more cities join the map: Boston, Kansas City, Omaha and Pittsburgh. Again, all but Omaha are filling gaps left by Spirit. The Boeing 737 MAX 8-200 will fly most of these services, though Pittsburgh gets a mix of the MAX and the Airbus A320.

The final two additions — Portsmouth and Providence — start in February 2027, and they show just how seasonal Allegiant's model really is. Each will be served only twice in February and April, with Portsmouth also picking up a single rotation in May.

That hyper-seasonality is worth knowing if you're booking. Some routes simply don't operate year-round. The Rochester flights stopped in May and won't return until October, while Chattanooga and Chicago Rockford are on pause this month. The whole point of the network is winter sun: flights run mainly October to May, shuttling snowbirds down from northern cities. Expect competition from Southwest and JetBlue on some of the routes, which can only be good news for fares.

The bigger picture: Florida dominates Allegiant's network. Its top three airports by weekly departures — Orlando Sanford (226), St. Petersburg Clearwater (174) and Punta Gorda (146) — are all in the state, ahead of Las Vegas (133) and Phoenix-Mesa (127). Fort Lauderdale sits sixth with 104 weekly departures in mid-October, but that's a 55% jump year on year, so the gap is closing.

For travellers in cities like Rochester, Trenton, Omaha or Providence, this means something rare: a nonstop to South Florida's beaches from airports other carriers skip. And if you're flexible on dates, the seasonal rhythm means the cheapest and most frequent service lands squarely in the winter months — exactly when a dose of Florida sunshine is most welcome. Just check that your chosen route is actually running in the month you want to fly, because with Allegiant, it very well might not be.