Regional airline Rex has leased six Boeing 737 planes as it prepares to take on Qantas and Virgin with flights between capital cities next year.
The airline has signed letters of intent for the planes, previously used by Virgin, that will fly between Brisbane, Sydney and Melbourne.
Rex has 60 Saab 340 aircraft but needs the bigger planes for the busier routes.
Deputy chairman John Sharp said three of the six 737s would fly in March when the airline started services between Sydney and Melbourne.
Management expects people will want to fly again as border restrictions for the coronavirus pandemic ease.
Another two planes would join services before Easter, he said. Rex aims to have 10 of the planes by the end of 2021.
The plan to expand services comes as Qantas and Virgin shed staff and costs in a tumultuous year for the aviation industry. Qantas has slashed flights and 8,000 workers, while Virgin entered voluntary administration before being bought by Bain Capital.
Mr Sharp said Rex hoped to gain regulatory approval by December. Ticket sales would follow.
He has previously said flights will include baggage allowance and meals.
Two lessors are providing the bigger craft, although Rex has not disclosed their identities.
Investment firm PAG Capital is funding the domestic Rex services.