Billy Gilmour has had his Chelsea contract extended until 2024.
The English Premier League side have exercised an option to add a further 12 months to his deal at Stamford Bridge.
The midfielder, who turned 21 on Saturday, spent last season on loan at Norwich City as he gained some valuable first-team minutes.
Sign up to Glasgow Live newsletters for more headlines straight to your inbox
To date the youngster has made 22 appearances for Chelsea's top team since joining from Rangers back in 2017.
Gilmour made his full Scotland debut last June and put on a man of the match display in the Euro 2020 draw with England at Wembley.
He has since established himself as a key member of Steve Clarke's squad and is currently with the team travelling to face Armenia.
He started the World Cup play-off semi final defeat to Ukraine at Hampden earlier this month and was introduced as a second-half sub last time out in the Nations League defeat to the Republic of Ireland.
Gilmour was handed his full Chelsea debut in a home game against Sheffield United in 2019, not long after his 18th birthday, and then signed a four-year deal with the club.