The group has been on hiatus since 2016, not long after Zayn Malik bid farewell to his bandmates, and every now and then some buzz about a possible reunion starts to build.
"We've had three or four group chats," he told E! News.
"Some of them have been more quiet than others. This new one is definitely louder than most, and it's been great. I'm sure if I had a look at my phone in a few minutes I'd see some messages."
Fans are now convinced it means the longed for reunion is on the horizon, posting messages on Twitter begging the What Makes You Beautiful singers: “Make it happen!”
Band got together on The X Factor
Styles and co have now been apart and doing their own thing for seven years.
The group got together on The X Factor in 2010 after auditioning as solo candidates.
Simon Cowell and co spotted their potential and put them together, and although they didn’t win the TV competition (losing out to Matt Cardle) they went on to have huge success.
They have had a string of chart-topping hits including Gotta Be You, One Thing and Live While We're Young and have sold more than 70 million records.
The stars have also won a raft of accolades, including Billboard Awards, Brits and MTV Awards.
When did they split?
In 2015 Malik announced that he was leaving the group, saying that he was sorry to upset fans but that he had to do “what feels right in my heart”.
He said he wanted some time out of the spotlight and any rumours of unhappiness were played down.
The band went on as a foursome but months after Malik left rumours of a break started to swirl, and in August that year they confirmed they would be going on hiatus in 2016.
However, Horan and co stressed that they weren’t splitting, just made it clear that they were taking a break.
What have they been doing since then?
Since they went their separate ways, all five of the stars have pursued solo careers.
Each band member has enjoyed success but it is Styles who has made the biggest splash, breaking records and carving out a spot for himself on the music A-list.
He has unveiled three albums – Harry Styles, Fine Line and Harry’s House – which all topped the charts in America.
Harry’s House scooped the Grammy for Album of the Year this year, and the 29-year-old's As It Was topped the Billboard Hot 100 for 15 consecutive weeks.
Three have become dads
Three members of One Direction have become dads since the band went on hiatus.
Tomlinson shares seven-year-old son Freddie with stylist Briana Jungwirth, who he is no longer in a relationship with.
Payne has six-year-old son Bear with his ex Cheryl, and Malik has two-year-old daughter Khai with US model Gigi Hadid.
Malik said on a US radio show after she was born that he’d adapted to fatherhood pretty easy.
"A lot of people that I was speaking to, obviously before she was born and stuff, were like, 'It's a big adjustment, and it's going to be a massive change and stuff'," he said.
"But honestly, she's an amazing baby."
What has been said about a reunion?
Rumours about One Direction getting back together start up every now and then, often on the back of an anniversary.
Things really heated up in 2020 when they launched a new official website to mark their 10th anniversary, with fans hoping for a tour.
However, so far they have not all performed together since 2015.
The singers are frequently quizzed about a reunion though, and have suggested it is a real possibility.
Styles was asked about it when he appeared on the final episode of The Late Late Show, and admitted he’d “never say never”.
“If there was a time when we wanted to do it, I don’t see why we wouldn’t,” he said.
And Tomlinson told The Times in an interview earlier this year: "Getting back together at some point is hard to imagine right now. But I’d be surprised if we lived out our lives and didn’t have a moment where we had a reunion, or whatever you want to call it. I’d be up for that.”
Watch: One Direction chatting on 'WhatsApp' group amid report band had music studio mini-reunion