The band, whose new album is out on 22 November, released the songlist in the North Wales Daily Post.
Lead guitarist Jonny Buckland tweeted the story from the band's account, explaining: "I once had a holiday job at the Daily Post, placing photos of houses for sale. I wasn't very good at it."
Though born in North London, Buckland grew up in Flintshire, Wales.
The band dropped a hint about the method of release when they announced the album earlier this week.
Posting a photo message on Twitter, they teased: "In the classifieds you might write, double album for sale, one very careful owner."
The typed letter had been sent to some select fans of the band, who shared theirs on Twitter.
Fans compared the letter from their musical heroes to getting a letter of acceptance from Hogwarts.
The Daily Post revealed the tracklist ad appeared alongside items for sale including a fridge freezer and a bale of hay, and below a Welsh Government public notice.
Songs include Sunrise, Church, Cry Cry Cry, and Old Friends.
Coldplay's last album, A Head Full of Stars, came out in 2015.
© Sky News 2019