Everton have confirmed that the paperwork for Allan's permanent transfer to Al Wahda in the United Arab Emirates has been completed.
The Brazilian midfielder, who joined the Toffees from Napoli for £21million two years ago, has not featured for Frank Lampard's side in the Premier League this season.
Allan fell down the pecking order at the Merseyside club after Lampard brought in three new midfield signing this summer.
Allan passed his medical and agreed personal terms with Al Wahda over the weekend prior to finalising his contract on Sunday.