Qantas will launch year-round flights between Sydney and Osaka's Kansai Airport, extending the previously-announced three month seasonal service, as travel between Australia and Japan continues to boom.

Starting December 14 2017 there'll be three flights per week in each direction using an Airbus A330 aircraft fitted with the airline's latest Business Suites in business class.

That provides passengers at the pointy end will fully-flat beds and direct aisle access from every seat, along with plenty of storage space and ample room to work during the day.

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Qantas flight QF33 will depart Sydney at 9:30am on Thursdays and Saturdays to reach Osaka at 5:25pm, while on Mondays, passengers will leave Sydney at a more leisurely 1:25pm for a 9:20pm touchdown in Osaka.

On the return, QF34 is wheels-up at 6:55pm on Thursdays and Saturdays ahead of a 6:45am arrival into Sydney the following morning. On Mondays, that's pushed to a 10:50pm departure out of Osaka for a 10:40am arrival in Sydney the next calendar day.

However, from 26 March 2018 the Thursday service will change to Wednesday, resulting in a weekly schedule of Monday, Wednesday and Saturday.

Business class passengers, Gold and Platinum frequent flyers and Qantas Club members will enjoy access to the international Japan Airlines Sakura Lounge in Osaka before their flight home (pictured below)...

... with Qantas' international business class lounge in Sydney also opening its doors to these travellers before Osaka-bound flights, with Platinum members enjoying access to Sydney's Qantas First Lounge as usual.

These flights can also be booked using Qantas Points (subject to reward availability), with many flights having three business class reward seats available and the majority having nine or more economy seats open for booking using points.

A business class return trip will set you back 144,000 Qantas Points plus $515.42 in taxes and fees, while in economy, that's reduced to 70,000 Qantas Points plus $335.42 in taxes and fees – although Qantas' current economy sale fares of $699 return may prove better value than using points if flying down the back.

The news follows Qantas' launch of year-round Melbourne-Tokyo flights in December 2016 and Brisbane-Tokyo flights in August 2015, complementing the airline's long-running Sydney-Tokyo route and making the Qantas the only airline flying non-stop between Sydney and Osaka.

Qantas' Oneworld partner Japan Airlines also offers Sydney-Tokyo flights and will begin Melbourne-Tokyo flights in September, while the Roo's low-cost arm Jetstar flies to Osaka from Cairns in North Queensland and to Tokyo's Narita Airport from both Cairns and the Gold Coast.

This article was updated on September 14 2017 to reflect the shift from seasonal to year-round flights.