The 1975 will replace Lewis Capaldi at the 2023 Reading and Leeds festivals.
While performing at the TRNSMT festival in Scotland on Sunday, the band's lead singer Matty Healy announced they will be taking over the Scottish singer's slot at the British music events after Lewis dropped out of all performances to focus on his health.
"So, on Saturday at Reading and Sunday at Leeds in celebration of our debut album, The 1975 will be playing that album in full support of our good friend Lewis Capaldi," the 34-year-old told the audience. "If you've got tickets, good for you. If you haven't, go and get them. We'll see you there."
Reading & Leeds organisers later confirmed the replacement and that the band will perform their 2013 self-titled debut album in its entirety to mark its 10th anniversary.
The band headlined last year's twin-site festival, while the 2023 headliners include Billie Eilish, The Killers, and Sam Fender.
Lewis announced in June that he would be taking a break after he struggled to finish his recent Glastonbury performance due to his Tourette's syndrome.
Matty recently gave a shout-out to his good friend during a show in London's Finsbury Park.
"I want to send my sincerest thoughts to Lewis Capaldi, who is a good friend of mine. Who on the day when he had to cancel his tour, checked in on me. Just think about that," he told the crowd.
"And it's also a reflection on how hard being a solo artist is as I would not be doing this show if I didn't have these amazing men and women behind me."