The England goalkeeper has put pen to paper on a new four-and-a-half-year deal that will keep him at Goodison Park until 2027.
Pickford, who had been due to enter the final 12 months of his contract this summer, has made more than 200 appearances for Everton since joining in 2017 and has established himself as the first-choice goalkeeper for England.
He told evertontv: "It's massive to sign this new contract at such a special club for me. The support I've had from everyone at the club since I joined as a 22-year-old has been so important to my family and me. I'm happy here and so are my family. We love it at Everton.
"Everton is a massive club. The past few seasons have not been what we wanted but we now have a manager who I believe will point us in the right direction and get us up the table.
"It's definitely my aim to be successful at this club. The fans, the staff and my teammates have been great with me from the moment I joined and I want to be great for them."
Pickford is determined to create a "legacy" with the Toffees as they prepare to move to a new stadium in the coming years.
He said: "I just want to keep working hard and performing for Everton. We know we are in a tough place at the moment in the league but I'm eager to help the team improve this season and then aim for success in the future, which will include playing in our new stadium.
"This contract will take me to more than 10 years at Everton and I want to build a legacy here to put myself up there with the likes of Neville Southall to be one of the best 'keepers to have played for Everton."