Bookings have opened for the first 17-hour flights.
Qantas is to run a daily service on the route from Heathrow to Western Australia from March 25, 2018.
The airline is to deploy new Boeing 787-Dreamliner on the route.
The direct flights form part of a new London-Perth-Melbourne return service by the airline.
The new QF9/QF10 will replace Qantas’ existing London-Dubai-Melbourne services – marking the next evolution of the ‘kangaroo route’, seven decades after the national carrier first flew British passengers to Australia.
Year-round return economy fares for the London-Perth route start at £1,095, but these are expected to drop below £900 return during deal periods.
Premium Economy fares lead-in at £2,335 and £4,240 for business class.
Qantas Group chief executive Alan Joyce said there had been global interest in the London-Perth flights since they were announced in December.
“We’ve said the Qantas Dreamliner is a game changer, and that’s becoming real today,” he said.
“The kangaroo route has kept changing with new technology. It used to take four days and seven stops but now we’re able to link the UK and Australia in a single hop. It’s a level of convenience those in Europe have never had before.”
He added: “We’re conscious that this is a long flight, but not much longer than our Sydney to Dallas service. It’s the kind of route that the Dreamliner was created for, because of its built-in features to reduce jetlag and improve the overall travel experience.
“We’ve added a very high level of comfort in each of the cabins and a lower seat count than most of our competitors. And we’re making tweaks to our in-flight service designed to help customers enjoy the journey more.”
Joyce said direct routes tended to stimulate new travel demand by making it easier to get to a destination – something that will benefit the UK, Western Australia’s economy and Australian tourism more broadly.
“This route makes Western Australia a new tourism gateway for Australia,” he said.
“We know from our research that there’s a lot of appetite to explore the west, not just from British and European visitors but also from Aussies on their way to London. A lot of business travellers, particularly in the resources sector, will stop off in Perth on their way to the UK.”
Qantas is building a new lounge at Heathrow Terminal 3 to accommodate 230 people and a new transit lounge at Perth airport.
By swapping its daily Airbus A380 London-Dubai-Melbourne service for a daily Boing 787-9 London-Perth-Melbourne service, Qantas has made the state of Victoria the hub for its first four Dreamliners.
Qantas’ first two 787s will be dedicated to the Melbourne-Los Angeles route from December 2017, with the third and fourth aircraft dedicated to London-Perth-Melbourne service from March 2018.
With a faster flying time and quicker connections in Perth, passengers travelling from London to Melbourne will reduce their total travel time by approximately an hour compared with existing Qantas A380 services.
The Qantas A380 that currently operates the London-Melbourne route will be redeployed to meet periods of high demand from Melbourne and Sydney to destinations in Asia, such as Singapore and Hong Kong.
The Qantas Emirates partnership will continue with passengers having the option to fly with the UAE carrier to Melbourne via Dubai from nearly 40 destinations in Europe.
Emirates is deploying an A380 instead of a Boeing 777 on its third daily flight from Dubai to Melbourne from next March.