Qantas Airways Ltd has been fined $A20 million for price fixing in the airfreight market.
The federal court in Sydney handed down the fine on Thursday, which the airline had agreed to when the Australian Competition and Consumer Commission launched legal action against it in October.
Qantas admitted "understandings" with other airlines on fuel surcharges relating to air cargo between 2002 and early 2006.
The airline said at the time the price fixing did not relate to its passenger service.
The court also on Thursday fined British Airways $A5 million, after it admitted an illegal arrangement in the airfreight market, over the same time period, with Lufthansa.
ACCC chairman Graeme Samuel said on Thursday the penalties sent a strong message to cartels.
"Cartels - particularly those that are engaged in by large businesses with broad application over a period of time - have a significant effect on consumers," Mr Samuel said. "They are an unseen fraud on the community that must be uncovered and punished."
Both Qantas and British Airways have been restrained from engaging in similar conduct for three years and ordered to pay $A200,000 each towards the ACCC's costs.
