England fly-half Marcus Smith has extended his contract with Harlequins beyond the 2023-24 season.
The 24-year-old has made 140 appearances and scored 1,287 points for the Premiership side since his debut in 2017, aged 18.
Playmaker Smith has become a regular in the England squad and has been capped 21 times in the past two years.
He is currently part of England head coach Steve Borthwick's training squad for this autumn's World Cup.
Smith was part of the Quins side that won the Premiership title in 2021 but the south west London club finished sixth in the table last season, missing out on the play-offs.
"I love the club, it's been my home since the age of 14 and I want to repay the faith shown in me and help Quins win trophies," Smith told the club website.
"We have unfinished business, we want to challenge for titles and create more memories for our supporters."
Quins director of rugby Billy Millard added: "We're delighted Marcus has extended his contract. He is a key member of our squad who displays outstanding commitment to his training and game development."
Harlequins have not disclosed the length of Smith's extended deal.