He started his career with FC Servette in his home, Switzerland, playing a few matches before joining Newcastle United as a 17-year-old.

After making his senior debut as a half-time substitute in the League Cup early in the 2015/16 season, Mbabu was given his first Premier League start three days later.

Mbabu joined newly promoted Premier League team Fulham on a three-year deal on July 27, 2022, with the option to extend for twelve months.