Independence occupies 35 gates in the coveted Concourse A at Dulles, six in Concourse B and shares two more.
The airport has not yet determined how to award the gates, and an executive made only a brief statement about the loss of Independence, which has a 23 percent market share at Dulles.
"Our Washington market is a very strong one that has attracted numerous carriers including Independence Air, who has been a great partner at Dulles providing excellent service and demonstrating the high demand for low-fare airline service," said James E. Bennett, president and chief executive of the Metropolitan Washington Airports Authority, which oversees Dulles and Reagan National Airport. "We will continue to work with our many airlines at Dulles to meet the domestic and international air service needs of the region."
None of the experts or airlines could say yet who would add service.
AirTran, which serves BWI, Dulles and National, is looking at where it might expand.
"We haven't made any decision about that, but certainly we're taking a look at it," said Judy Graham-Weaver, an airline spokeswoman. "We monitor market conditions, and certainly when an airline goes out of business, market conditions change."
She noted that the airline rapidly expanded at BWI after the 2001 terrorist attacks led to US Airways' retreat there, and is now BWI's second-largest carrier.
Hugo Burge, president of Boston-based cheapflights.com, an online fare finder, said the airlines are becoming more discriminating about new routes or extra flights now that some of the competition - and pressure to cut fares - is easing.
"Airlines are being smart about which routes they do and don't do," he said. "This is sad news for some consumers, but it's probably welcomed by the aviation industry. This does mean we'll probably get healthier, stronger airlines, and that's for the good of consumers as well."
Independence ticket holders
The airline will continue flying until 7 p.m. tomorrow and will honor all tickets until then.
If you have a reservation after then, the company is seeking bankruptcy court approval to automatically refund the fare.
If you have a round-trip reservation that departs before the scheduled cessation of service and returns afterward, you will be contacted by Independence Air and offered a chance to change your return flight at no extra charge. Passengers who change their own reservations on the carrier's Web site may have to pay a difference in fare costs.
For those not rescheduled in time on Independence, the airline is seeking the court's approval to automatically refund the fares.
There will be no refunds for free tickets or vouchers, though the tickets will be honored as long as the airline flies.
Federal law requires other U.S. airlines flying the same routes to offer stand-by seats to passengers holding unrefunded tickets for airlines that have ceased operations due to bankruptcy if contacted within 60 days. They may charge $50 one way per person.
If you've provided goods or services to Independence, the carrier intends to pay its bills.
Customers can call the airline at 800-359-3594, but expect long wait times. The company is encouraging people needing information to go to its Web site, www.flyi.com.
Carriers at BWI have suffered from the competition Independence Air created since it began flights at Dulles in June 2004.
Southwest acknowledges that the move to Dulles is atypical and that some business will shift from BWI. About 10 percent of BWI passengers drive in from Virginia.
Analysts see growth for carrier, local economy
D.C. will become SWA's second new market this year after it launched service in Denver in January.