Jetstar is offering discounts to passengers without check-in baggage, and Tiger Airways is selling 100,000 seats at $9.95 each.
The two airlines are competing for business in what analysts say is a softening market.
Under the Jetstar offer, Jetsaver Light, passengers without check-in luggage get a $10 discount on its cheapest fares and $20 off on international fares. The allowance for carry-on baggage has increased to 10kg from 7kg.
Jetstar chief executive Alan Joyce says he believes the offer will appeal to business and short-break travellers.
But if you change your mind as to what you’d like to bring home with you, you’ll have to pay the difference plus a $10 change fee. And the discount is not available for more flexible fares.
Subscribers to the Jetstar newsletter were also offered 5000 one-cent fares on six interstate routes.
Tiger offered 100,000 tax-inclusive one-way $9.95 fares on 12 routes, including 15kg luggage allowance.