Vaitai has agreed to a five-year, $50 million contract with the Lions, Adam Caplan of SiriusXM Radio reports.
Vaitai spent his first four seasons with the Eagles after getting drafted in 2016. He has not missed a game since his rookie season. The 26-year-old will now begin a new chapter in his career with the Lions.
Vaitai (knee) wasn't listed on Wednesday's injury report.
Vaitai is expected to return to his role as Lane Johnson's backup at right tackle Sunday versus the Redskins.
Vaitai is recovering from a knee injury, but it isn't considered serious, Les Bowen of the Philadelphia Daily News reports.
This is fortunate news for the Eagles, as Vaitai is their top reserve tackle. However, it isn't clear when he'll be able to return to the practice field during training camp.