It's official. After almost 16 years, the Friends cast will be reuniting for an as-yet-untitled unscripted special.

Jennifer Aniston, Courteney Cox, Lisa Kudrow, Matt LeBlanc, Matthew Perry and David Schwimmer will shoot the show to mark the launch of HBO Max.

"Guess you could call this the one where they all got back together — we are reuniting with David, Jennifer, Courteney, Matt, Lisa, and Matthew for an HBO Max special that will be programmed alongside the entire Friends library," said HBO Max chief content officer Kevin Reilly.

The news was posted by Cox, who played Monica Geller, on Instagram. Her post attracted more than 650,000 likes inside an hour.

Various sources are reporting each cast member will get almost $4m for the show.

The show, about the lives and loves of six close-knit young people in New York is billed as a "celebration" of the series than ran for 236 episodes over 10 series after its launch in 1994.

"I became aware of Friends when it was in the very early stages of development and then had the opportunity to work on the series many years later and have delighted in seeing it catch on with viewers generation after generation," said Reilly. "It taps into an era when friends – and audiences – gathered together in real time and we think this reunion special will capture that spirit, uniting original and new fans."

Friends not only won the Emmy for outstanding comedy series, but also garnered Emmy awards for Aniston and Kudrow.

HBO Max is a new streaming service set to launch in the US in May. It's unclear whether it will be available in New Zealand and how Kiwi fans might be able to watch the new show.