"It's incredible to join Everton," Coady, who spent the past seven years at Wolves and captained the team for the last four, told the club's TV channel.
"As soon as I heard the interest, from the manager (Frank Lampard) but also the Football Club itself, I really wanted to be part of it straight away. I'm over the moon to join.
"I've grown up around the city... I'm someone who was desperate to come here. I've got family and friends who are massive Evertonians."
Coady joined Wolves as a midfielder in 2015 from Huddersfield Town and was transformed into a central defender under former Wolves manager Nuno Espirito Santo (48). He made 317 appearances in all competitions for the club.
"Conor has been an integral part of our success over the last five seasons," Wolves chairman Jeff Shi said.
"His dedication to Wolves in that time means that we choose not to stand in the way of his desire to play football elsewhere, and he leaves with our best wishes."
Coady has 10 England caps, making his debut in August 2020 in the Nations League match against Denmark.
"I'm here to give absolutely everything I've got for this football club. It's important I work as hard as I can to ... help the club move forward and make people proud," he said.
Coady is Everton's fourth signing of the current transfer window after the arrivals of defender James Tarkowski (29), former Wolves teammate Ruben Vinagre (23) and forward Dwight McNeil (22).
Everton continue their Premier League campaign with a trip to Aston Villa on Saturday, August 13th.
