Quarantine-free travel between New Zealand and Australia is on again, more than a year after Covid-19 closed the borders.

The trans-Tasman bubble opened this morning, with the first Air NZ flight from Wellington to Sydney leaving at 6.05am and the first Auckland to Sydney flight at 7.30am. 

The first scheduled flight from Australia, Jetstar flight JQ201 from Sydney, is due to land at Auckland Airport at 11.20am.

About 2000 people are expected to fly from New Zealand to Australia, while 3000 are coming in the other direction throughout the day.

There'll be many tearful reunions for family and friends, separated by the deadly pandemic, while there will also be some brave holiday makers on the flights.  

Queenstown Airport will welcome its first international scheduled commercial flight at 2.30pm today. 

Qantas flight QF121, an Airbus A320, is due to touch down from Sydney before the return flight, QF122, leaves an hour later.  

They will be the first of 36 trans-Tasman flights this week, connecting Queenstown to Sydney, Melbourne and Brisbane. About 40 flights a week are expected until it ramps up for the ski season.  

Prime Minister Jacinda Ardern said: "It is truly exciting to start quarantine-free travel with Australia. 

"Be it returning family, friends or holiday makers, New Zealand says welcome and enjoy yourself.

"The bubble marks a significant step in both countries reconnection with the world and it’s one we should all take a moment to be very proud of."

Only Air New Zealand, Qantas and Jetstar are operating at this stage. 

Arden and and Australian PM Scott Morrison issued a joint statement saying the trans-Tasman quarantine free travel is a "world-leading arrangement that opens up travel while aiming to keep COVID out of the community".

"Fulfilment of our commitment will allow many friends and family across the Tasman to re-unite for the first time in over a year," the statement reads.

"Our countries share a Single Economic Market, and two-way travel across the Tasman will help drive the economic recovery for both countries while we continue to navigate the COVID-19 global pandemic, especially in the travel and tourism sectors.

"It will also enable closer trans-Tasman business engagement, which will drive broader economic activity in both Australia and New Zealand."

Morrison says today's milestone is a "win-win for Australians and New Zealanders, boosting our economies while keeping our people safe and just in time for ANZAC Day".

“Both countries have done a remarkable job in protecting our communities from COVID and two-way flights are an important step in our road out.”

Australia and New Zealand are also exploring opportunities to extend quarantine-free travel to other countries in the Pacific, when it is safe to do so, reflecting our close ties to the Pacific and our commitment to supporting their recovery.

Travellers will need to be prepared for possible disruption to travel arrangements at short notice and to follow specific protocols before, during and after their travel. Information for travellers can be found on New Zealand's Unite Against COVID-19 website.