The teenage defender played his part in the club’s treble-winning season – making 23 appearances and earning high praise from Pep Guardiola.
Now he has committed his future to the champions until 2028 – with the option of a further 12 months at the end of it.
Lewis – a boyhood City fan – has been on an academy wage of around £5,000 per week and his new deal will see it rise significantly to around £25,000 per week.
As well as making the breakthrough last season, he became the youngest player to score in the Champions League on his full debut against Seville in November.
Lewis, 18, said: “It’s been an unbelievable year for me and now to sign this contract is a dream come true.
“As a City fan I can remember watching us winning trophies when I was young and it’s the only place I’ve wanted to be.
“To know I’m going to be here until 2028 is fantastic and I can’t wait to keep working and keep improving.
“Everyone at the Club has been so amazing, starting with the Academy where I learnt so much and I am hugely grateful for everything they did.”
City have also tied Nathan Ake to a new deal this summer – and are working on contract extensions for Kyle Walker and Bernardo Silva.
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Director of football Txiki Begiristain said: “We are very proud to have watched his journey through the Academy and to see him playing with such confidence in the first team.
“His energy and hunger around the squad is contagious and we believe he can help to bring more success in the coming years.”
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