United Airlines is stretching its narrowbody fleet further than ever. Cirium schedule data for January 2027 shows the Star Alliance carrier's longest Boeing 737 MAX routes topping out at around 3,000 miles — distances once reserved for widebody aircraft. For travellers, that means more nonstop options to leisure destinations without paying widebody prices baked into fares.

The single longest run is San Francisco to San José, Costa Rica, an eight-hour flight of just over 3,000 miles connecting Northern California with Costa Rica's capital region and Central Valley. Close behind is San Francisco to Liberia (2,946 miles), which serves the Pacific-beach resort belt of Guanacaste. Having both routes means West Coast flyers can pick between city-and-volcano itineraries and straight-to-the-beach holidays.

The rest of the long-haul list reads like a winter-sun brochure. Houston flies nonstop to Georgetown, Guyana (2,901 miles) — handy for the country's growing energy sector and its large diaspora. Chicago O'Hare reaches Anchorage (2,846 miles), gateway to Alaska's outdoors. Denver links to both San Juan, Puerto Rico (2,732 miles) and Punta Cana in the Dominican Republic (2,609 miles), giving inland US travellers one-stop-free access to the Caribbean in peak season.

Transcontinental flying features too: San Francisco–Boston clocks in at 2,704 miles, while Los Angeles offers long MAX routes to San José and Liberia in Costa Rica plus Lihue on Kauai (2,615 miles) — an overwater sector that demands careful fuel and diversion planning. At the other extreme, United also uses the same jets on hops under 250 miles, such as Houston–San Antonio (191 miles) and San Francisco–Reno (192 miles), showing how the type slots into everything from short regional shuttles to near-long-haul services.

The fleet behind this is substantial: United operates 304 MAX 8s and MAX 9s, with more MAX 9s on order and 167 MAX 10s pending. The economics are the point — the MAX's range and fuel efficiency let United serve thin-but-real long-haul demand without committing a widebody to every departure, which usually translates into more frequency and more competitive fares on routes like these.

Note the caveats: schedules and aircraft swaps can change before departure, so it's worth confirming the equipment on your specific date if the aircraft type matters to you. And in summer, United pushes the MAX even further across the Atlantic to places like Glasgow and Santiago de Compostela.

For holidaymakers, the takeaway is simple: if you're eyeing Costa Rica, the Caribbean, Hawaii or Alaska from a US hub for winter 2027, chances are good your nonstop will be on one of these narrowbodies — often with a smaller cabin, quicker boarding and no connection needed.