Maupay is Everton's sixth signing of the close season after James Tarkowski, Ruben Vinagre, Dwight McNeil, Conor Coady and Amadou Onana and joins for an undisclosed fee.
The Merseyside club had hoped to seal the transfer in time for the 26-year-old to make his debut on Saturday at Brentford but did not complete the paperwork in time. "It feels amazing," said Maupay. "It was an easy choice for me when I started to talk with the club.
I knew straight away I wanted to play for Everton and help the club to succeed. "I'm excited and it's a new challenge for me.
I will do everything I can for Everton," added the striker, who scored 26 goals in 102 league games for Brighton. Maupay, who moved to the south-coast from Brentford for 16 million pounds ($18.78 million) in 2019, regularly finished as Brighton's top scorer but manager Graham Potter said he had left for football reasons after not playing so far this season. "Neal is keen to play more regular football than we have been able to offer and Everton are able to give him that opportunity.