James Ward-Prowse has signed a new five-and-a-half year contract with Southampton.
The 20-year-old academy graduate, who joined Saints aged eight, said he was "buzzing" to agree a deal until 2020.
"The club put their faith in me at a young age," said Ward-Prowse. "I can't wait to pay that faith back to the club and the fans."
He has played 17 times for Southampton this season, who sit third in the Premier League.
He said: "You only have to look at the players we've produced over the last few years to see it is the right place.
"There's not many clubs in the country, or the world, who give young players the chance to play in the biggest league in the world."
Ward-Prowse made his debut for Saints in a Capital One Cup defeat to Crystal Palace in October 2011 and helped the England Under-21s qualify for the 2015 European Championships this summer.
Southampton manager Ronald Koeman said: "I'm happy he would like to stay with us. It's a good signal to the rest of the players. He's one of the examples for the academy, to the confidence of the young players."