The band are going to release a double album on November 22nd called sunrise and Sunset announced in a letter sent to a fan.
"For the last 100 years or thereabouts, we have been working on a thing called Everyday Life," said the band in the typewritten message.
The letter was signed by all four members of the band, it's recipient initially thought it was a hoax.
Lena Tayara said "Fake Alert!" on Twitter, alongside a picture of golden letter.
"Got this in the post this morning... Can't see why anybody would send it."
Fans quickly reassured her it looked authentic, then she changed her mind, writing: "If I'd known that card was genuine I would have put on a nicer tablecloth before I took the pics.
"But thanks for the card - I'm AMAZED and very touched."
Coldplay one of the biggest selling UK bands of the 21st century last release was the 2015 Album a Head Full of Dreams, an uplifting more dance and pop orientated album which is a long departure from the sound of their first album Parachutes in 2000.
Other than a Head Full of Dreams, Coldplay did work with Pharrell Williams on the Kaleidoscope EP under the name Los Unidades.
Rumours of a new album were sparked last week when black and white posters of the band appeared in the Spanish capital Madrid showing them as a 1920s wedding band. The band then shared a video showing the black and white picture found in Madrid with orchestral music and the words "November 22nd, 1919".
That post was followed by a new profile picture on the bands Twitter account the sun and the moon, which we know reflect the double albums title.
Very little else is known about the record but last year, frequent collaborator Mat Whitecross told the NME it would "surprise people", while an unnamed "insider" recently told the Daily Star the album would be showcase their "experimental side".
Coldplay fans mark the 22nd November in your calendars for new material from Chris Martin and co.