Roberto Martinez has been a long term admirer of the 27-year-old, and announced his signing by parading him in front of surprised fans at Goodison Park before the Toffees’ 2-0 win over Norwich on Saturday.
The former Celtic man arrives with bags of Champions League and international experience, ready to help Everton in their push for the top four during the second half of the season.
Reports suggested McGeady would sign a pre-contract agreement and move to Merseyside in the summer, but Martinez has been quietly working to complete the deal earlier.
He is set to compete with the likes of Kevin Mirallas and Steven Pienner for a starting position out wide, with the Toffees currently occupying fifth spot in the Premier League, just a single point outside the top four.
The winger spent six trophy-laden years at Celtic, before making the switch to Russia in 2010 in a move worth £9.5million.
He is set to link up with international team mates James McCarthy, Darron Gibson and Seamus Coleman following his move to Goodison Park.