"Since launch day, Afterpay has been incredibly popular among our customers in Australia, with thousands of bookings in the first month," a Jetstar spokesman said.
"With Christmas only weeks ahead, we decided to expand this option for more travellers by making Afterpay available for bookings four weeks in advance of travel."
The airline said it was also working towards offering Afterpay on international flights.
"We've heard from many customers wanting to include Afterpay on international flights and that's a possibility we're exploring for the near future and will announce opportunely," the spokesman said.
The Afterpay service is available for transactions between $200 and $1000, booked four weeks or more in advance of travel, and a service fee of $10 applies.
When the game-changing partnership between Jetstar and Afterpay was first launched in September, Jetstar Group's chief executive Jayne Hrdlicka said the low-cost carrier was the first airline in Australia to offer it.
"Our mission at Jetstar is to offer low fares to enable more people to fly to more places, more often. Partnering with Afterpay gives our customers the option to lock in low fares at today's prices and pay over time, even during our sales," she said.
"Many of Jetstar's customers already use Afterpay to purchase items at various retailers and are familiar with the flexibility of paying over time."
To take advantage of Afterpay, customers simply choose a fare on the Jetstar website and select the Afterpay payment option.
The booking will be made with the fare price locked in, and the flight itinerary will be sent.
Customers can then make regular repayments and go on their trip.
