The Australian Competition and Consumer Commission has received hundreds of complaints from passengers whose flights were suspended or cancelled because of travel restrictions but were given credit, not refunds.

"From our perspective, from the outset, Qantas did not communicate clearly with customers about their rights and in a large number of cases, simply omitted they were entitled to a refund," ACCC chair Rod Sims said in a statement on Friday.

"In some cases, the ACCC considers Qantas' emails may have encouraged these customers to cancel bookings themselves in order to receive a credit when many would have been eligible for a refund."

Mr Sims said a new email Qantas has sent to customers in recent days - to "remind" customers about their refund rights - came after weeks of pressure from the ACCC.

But the watchdog said even that "is not particularly clear".

"... I think that customers can and should expect better from Qantas, particularly when many of those customers may be out of work or experiencing financial hardship," Mr Sims said.

"If any customer in this situation is unhappy with receiving a credit, or no longer wants one due to continuing uncertainty about when flights will resume, we strongly encourage them to contact Qantas and seek a refund."

Qantas said it did not think it's initial advice to customers was unclear.

"But we've written again to a group of customers in the window of time that the ACCC is concerned about to make sure they know what alternatives are available to them," the airline said in a statement.

"We hope the ACCC is not inferring that we haven't done the right thing by our customers, particularly given the efforts we have made to manage an exceptional level of upheaval."

The dressing down comes as Qantas and its subsidiary Jetstar try to reboot domestic travel by offering cut-price airfares and bonus points for frequent flyers.

Jetstar is offering 10,000 one-way fares for $19 on 22 routes, including Melbourne to Sydney, Sydney to Gold Coast, Melbourne to Ballina, Brisbane to Whitsunday Coast and Adelaide to Cairns.

Other routes have also been discounted but not to the same extent.

Qantas is offering triple points for frequent flyers on all routes, and customers of both airlines will also be given more flexibility to change flight dates without being hit with fees, the airlines said in a statement on Friday.

Australian Associated Press