Confirmation of the new deal for the 22-year-old came via the club's official Twitter account:
Having impressed initially, he fell down the pecking order at the Emirates Stadium and struggled to get regular minutes. In 2016-17, the youngster was sent out on loan to Middlesbrough, and while the team were relegated from the Premier League, Chambers was largely impressive in the north-east.
In the summer, he was part of the England side that played at the UEFA Under-21 European Championship.
Scouted Football were impressed with his displays at the heart of the Three Lions defence:
This season Arsenal kept the youngster around despite interest from Leicester City and Crystal Palace. According to David Ornstein of BBC Sport, the Gunners rejected two bids in the region of £20 million from the Foxes.
"Arsenal had been happy for Chambers to leave after telling him they could not guarantee him a place at centre-back," it was noted by Ornstein. "But their stance changed a month ago when Arsene Wenger decided he wanted to keep the 22-year-old."
This new deal suggests the Gunners do have faith in Chambers to fulfil the potential he showcased from an early age at the Emirates. However, he’s yet to make a Premier League appearance this season, with his only start coming in the Carabao Cup against Doncaster Rovers.