The promotion, four trips for the price of three, will be backed by full-page ads in national newspapers throughout the summer travel season.
Under the initiative announced today, customers who fly three eligible paid round trips between tomorrow and September 30 will earn a free round-trip ticket for travel in the 48 contiguous states this fall.
Since filing for Chapter Eleven bankruptcy last December, United has scored important gains in restructuring its labor contracts and airplane leases.
But it's still losing money, with the war in Iraq and the SARS virus adding to its challenges in a tough air travel market. United hopes to emerge from bankruptcy sometime next year.