The Istanbul club have officially announced the capture of the Netherlands international, bringing to an end the longest running transfer saga of the January transfer window
The Netherlands international will earn €2m in salary between now and the end of the current season before picking up €3.2m a year until the summer of 2016.
The 28-year-old will also be paid a €3.9m signing-on fee, plus €25,000 for every appearance he makes for Fatih Terim's side.
Sneijder can therefore earn an additional €2.5m if, for example, he makes 100 appearances for the club over the three-and-a-half years.
That means the total cost of the transfer for Galatasaray could be a staggering €25.5m.