The 25-year-old signed for the Toffees on a two-and-a-half-year contract on transfer deadline day for a fee that could rise to £40m.
Alli joined Spurs from MK Dons in the summer of 2015 and impressed particularly in his first two seasons at the club, reaching double figures for goals in both campaigns.
His form has dropped off in the last two seasons and he struggled for game time under Jose Mourinho and recently Antonio Conte.
Nonetheless, Alli has fond memories of his time in North London and has sent a message of appreciation to his former employers as well as former Spurs boss Mauricio Pochettino, who brought him to the club.
Alli wrote: 'It's the end of a chapter but not the book… Thank you all for the messages.
'I've had an incredible 7 years at Tottenham and have made some lifelong friends that now feel like family!
'I want to wish my brothers all the best for the rest of the season and more. To the fans, I want to say thank you.
'We've had some incredible moments together than will stay with me for the rest of my life and I will never forget the amazing support you have given me.
'Playing for you was a dream come true and you will always be in my heart.
'I want to give a special mention to Mauricio and his staff for their trust and guidance in the early part of my career at Spurs, which gave me the confidence and platform to show what I can do.
'I love you all and wish you the best for the future! Dele out.'
