Mac Allister has extended his contract with Brighton and Hove Albion until the summer of 2027, according to the club’s official website.
The 19-year-old midfielder joined the Seagulls in January 2020 from Scottish side Dundee United for a fee of £450,000. He made his debut in a 2-1 defeat to Manchester City on November 8, 2020, and went on to make 26 appearances for the club last season.
Allister is currently part of the England Under-21 team and has been capped by the national side at both under-19 and under-21 levels. He was also named in the PFA Young Player of the Year shortlist for the 2021/22 campaign.
Brighton manager Graham Potter said: "We're delighted to have secured Mac's future at the club. He's become an integral part of our squad and we look forward to seeing him continue to develop as a player."
Allister said: "I'm really happy to extend my stay at the club. I've had a fantastic time here so far and I'm looking forward to continuing to develop and learn more about football."