The 21-year-old Belgium international has signed a five-year deal with the Toffees after scoring 15 Premier League goals during a season-long loan at Goodison Park last term.
And Lukaku, who moved to Chelsea from Anderlecht in 2011, believes Everton is the perfect club for the towering striker to develop as a player.
“I’m 21, I need to be playing in a good team. I needed to be in a place that felt right,” Lukaku said.
“I had a feeling that this was the best place for me to grow, so I’m happy to be here again.”
Lukaku added: “I am really excited about rejoining Everton. I had a fantastic experience last season and a great relationship with the manager, the chairman, the staff, the players and the fans.
“I can’t wait to get started again and I’m looking forward to a successful season.”
Lukaku made just 10 Premier League appearances for Chelsea.
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