Services were scheduled to run on Saturdays between December 18 and January 19, but the Australian airline has pushed those flights out until April 23.
Destination Queenstown (DQ) general manager Tony Everitt said Queenstown Airport had clocked nearly the same passenger numbers in the first three months of this financial year as it did for the whole of the 2007-08 year.
Passenger numbers look set to spike on the back of the announcement that Jetstar and American Airlines have agreed to a code-share partnership, which aims to attract American Airlines' 50 million frequent flyers to New Zealand.
The deal allows customers to travel with Jetstar, Qantas and American Airlines on one ticket, between the United States and destinations from Auckland to Queenstown.
Mr Everitt said Qantas' extra flights and the code-share ticket deal between the three airlines showed a $2 million joint venture Australian promotional campaign - mainly targeting online and print media - between DQ, Tourism New Zealand and member partners was bearing fruit.
"The promotion has helped build demand and it's great that Qantas are acknowledging that," he said.
