Singapore Airlines made global headlines last year when it relaunched its Newark-Singapore flight. The 9,534-mile flight allowed the carrier to reclaim the title of having the “world’s longest flight,” bumping Qatar Airways and its 9,032-mile Doha-Auckland, New Zealand, flight out of the top spot.Another title shift could happen in the coming years if Qantas Airways decides to push ahead with its “Project Sunrise” flights. The Australian carrier made headlines of its own this fall as it tested several ultra-long flights to Sydney – including from New York and from London – to great fanfare. Each would be longer than Singapore’s current record-holder, and Qantas days it will decide soon whether to press ahead. If it does, flights could begin in 2023.But have you ever wondered what the longest flight is on your preferred carrier? Or the shortest? Given all the buzz about long flights recently, we decided to see what clocked in as the longest and shortest flights for each of the 11 biggest U.S. carriers.Sign up for the free daily TPG newsletter for more airline news.What did we find? Today we look at United, the last in our look at the 11 biggest U.S. airlines. Its longest route on the December schedule is Houston-Sydney while its shortest is the 66-mile hop it operates between San Francisco and the Charles M. Schulz–Sonoma County Airport near Santa Rosa, California.Previous: Alaska Airlines | Allegiant Air | American Airlines | Delta Air Lines | Frontier Airlines | Hawaiian Airlines | JetBlue | Southwest Airlines | Spirit Airlines | Sun Country AirlinesSign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.LongestHouston Bush Intercontinental (IAH) - Sydney, Australia (SYD): 8,591 milesSan Francisco (SFO) - Singapore (SIN): 8,433 milesNewark (EWR) - Hong Kong (HKG): 8,045 milesLos Angeles (LAX) - Melbourne, Australia (MEL): 7,922 milesMelbourne (MEL) - San Francisco (SFO): 7,857 milesCape Town (CPT) - Newark (EWR): 7,819 milesMumbai (BOM) - Newark (EWR): 7,790 milesNew Delhi (DEL) - San Francisco (SFO): 7,688 milesLos Angeles (LAX) - Sydney, Australia (SYD): 7,489 milesSan Francisco (SFO) - Sydney,Australia (SYD): 7,420 milesShortestSan Francisco (SFO) - Santa Rosa/Sonoma County, California (STS): 66 milesColorado Springs (COS) - Denver (DEN): 67 milesMilwaukee (MKE) - Chicago O’Hare (ORD): 67 milesCollege Station, Texas (CLL) - Houston Bush Intercontinental (IAH): 74 milesMonterey, California (MRY) - San Francisco (SFO): 77 milesCharlottesville, Virginia (CHO) - Washington Dulles (IAD): 77 milesChicago O’Hare (ORD) - South Bend, Indiana (SBN): 84 milesSan Francisco (SFO) - Sacramento (SMF): 86 milesLos Angeles (LAX) - Santa Barbara, California (SBA): 88 milesWashington Dulles (IAD) - Shenandoah Valley, Virginia (SHD): 91 milesSource: United Airlines. Flights based based on regularly schedule flights during the carrier’s December schedule. Next update: March 2020.Note: This post updates and replaces a previous post that looked at the longest and shortest flights offered by United.For more info about the airline, check out TPG’s United Airlines by the numbers post.