Washington DC (IAD) to Austin (AUS): 1,295 miles (2,084 km) great-circle, about 3h 05m nonstop by our estimate. Cheapest fare observed: $264 round-trip on Allegiant Air, nonstop, departing June 5, 2026.
$264 round-trip, Allegiant Air G4234, departing 2026-06-05 at 16:27, returning 2026-06-07. The recorded itinerary left on a Friday, returning on a Sunday 2 nights later; the fare was observed 41 days before departure. "Book this flight" opens Kiwi.com with the same airline and dates.
At $264, it ranked 7th of the 30 round-trip fares we recorded from IAD (median $775). That is 20.4 cents per great-circle mile (round-trip price over one-way distance), close to the IAD median of 22.5 cents across 30 round-trip routes.
Routes from IAD of similar length: Dallas (1,170 mi) at $268 and Denver (1,449 mi) at $156.
IAD to AUS is the only one of 30 IAD routes where Allegiant Air priced cheapest. It is the 23rd longest of the 30 routes we track from IAD.
Of 7 departure airports with a fare to Austin, Washington DC (IAD) ranked 4th at $264. Lowest: $190 from San Diego (SAN); highest: $1373 from Chennai (MAA); 3 nonstop. Cheapest-fare airlines (routes): Frontier (3), Allegiant Air (1), Copa (1), Emirates (1) and Spirit (1).
Travelpayouts fares (cheapest per route, observed April 25, 2026); OurAirports coordinates and elevations; IANA zones America/New_York, America/Chicago; flight time is our estimate.