Swift has surprised fans by announcing her ninth album evermore, which she describes as "folklore’s sister record", and it's arriving at midnight EST tonight (5am GMT tomorrow).

It appears that Swift worked with similar people on evermore, as she writes on Instagram that "we just couldn’t stop writing songs".

She adds, "I’ve never done this before. In the past I’ve always treated albums as one-off eras and moved onto planning the next one after an album was released. There was something different with folklore. In making it, I felt less like I was departing and more like I was returning."

Swift gave a shout out to folklore collaborators Aaron Dessner, Jack Antonoff, WB (William Bowery, aka her boyfriend Joe Alwyn), and Justin Vernon of Bon Iver.

The folklore artist also shared the tracklist for the album on Twitter, writing, "Ever since I was 13, I’ve been excited about turning 31 because it’s my lucky number backwards, which is why I wanted to surprise you with this now. You’ve all been so caring, supportive and thoughtful on my birthdays and so this time I thought I would give you something!"

The album will featuure 15 tracks, including new collaborations with Haim, The National and Bon Iver. Swift added on Twitter that "the deluxe physical edition will include two bonus tracks - "right where you left me" and "it’s time to go"."

The first video from the evermore album to be released will be "willow", which arrives at midnight EST / 5am GMT tonight/tomorrow.

Taylor Swift's evermore album lands digitally at midnight EST tonight / 5am GMT tomorrow (11 December).