Eder is joining Lille in a £4million move bringing to an end his unsuccessful stint at Swansea City.
The Portuguese international striker joined in a £5m deal from Sporting Braga last summer and was expected to provide competition for Bafetimbi Gomis.
But Eder never found the net in 15 appearances though he was mainly used coming off the bench and moved to the French outfit in a loan deal in January in a four-year deal.
Eder has bagged six goals for the Ligue 1 outfit while Bafetimbi Gomis could be the next striker out of the Liberty Stadium exit door.
The French striker was used mainly as a sub towards the end of last season and if Francesco Guidolin sticks with £8m singing Alberto Paloschi and brings in another striker, then Gomis will also be on his way.