Everton signed Leeds winger Jack Harrison on a season-long loan on Monday.
Harrison returns to the Premier League following Leeds' relegation to the Championship last season.
The 26-year-old becomes Everton's fourth signing since the end of last season after spending the last five years at Leeds.
"Jack Harrison passed his medical with the club yesterday before completing the necessary paperwork this morning," Everton said in a statement.
"He will now continue his rehabilitation from a minor hip injury before being available for Sean Dyche's squad."
Dyche had signed Arnaut Danjuma from Villarreal, Ashley Young from Aston Villa and Youssef Chermiti from Sporting Lisbon since his team narrowly avoided relegation last season.
Everton opened the Premier League season with a disappointing 1-0 home defeat against Fulham on Saturday.
Harrison, who joined Leeds from Manchester City, is the ninth player to leave the Elland Road club following their relegation.
He scored 34 goals in 206 appearances in all competitions for Leeds after making his debut in 2018.
Harrison helped Leeds win promotion to the Premier League in 2020 and signed a new five-year deal in April before the club's three-year stay in the top-flight ended in May.