The organisers of the Bristol International Balloon Fiesta say they are confident they will attract enough sponsors despite a slow take-up.
When the event lost its main sponsor in 2009 it sold deals to companies for £2,000 with one having the chance to become the festival's main sponsor.
A fiesta spokesman said 35 tickets had been sold with three weeks to go.
"We've got a lot of people we're talking to. We're hoping to give it a boost," said organiser Clive Bailey.
Last year nearly 50 companies backed the festival after organisers failed to attract a major sponsor.
The event takes place between 12 and 15 August at Ashton Court estate.