Maarten Stekelenburg will join Ajax on a permanent deal at the end of the 2019/20 campaign.
The 37-year-old’s Goodison contract was set to expire on 30 June, but he will remain with the Toffees until 26 July as cover for the rest of the season.
Stekelenburg, who joined Everton from Fulham in 2016, made 26 first-team appearances for the club and will rejoin Ajax having spent the first nine years of his professional career with the Eredivisie giants, where he helped them win two league titles and three Dutch Cups.