The Brazilian has moved to Goodison Park after agreeing a three-year deal.
Everton have announced the signing of Allan from Napoli, marking their first acquisition of the transfer window.
The Brazilian midfielder has agreed to a three-year deal after Everton paid a transfer fee of 21 million pounds.
Allan had been widely speculated to leave Stadio Sao Paolo this summer, with Carlo Ancelotti interested in a reunion.
The 29-year-old also looks excited about reuniting with his former manager as he spoke about the Italian manager after putting pen to paper.
“It is a real pleasure to sign for Everton. I am immensely happy to be here,”
“It is a club with a rich history in the Premier League, has real ambition and then there is ‘Professor’ Ancelotti.
“It is the size of the club and the name of the coach which means you don’t think twice about coming to Everton.”
Allan has tons of experience under his belt as he had played more than 200 matches with Partenopei for around five years.
The Toffees are also said to be closing in on the deals for James Rodriguez and Abdoulaye Doucoure.
James’ contract with Real Madrid expires next year and he has already revealed his intentions to leave the club.
The Colombian would likely cost Toffees around 22 million pounds.