Thomas caught six passes for 65 yards in the first two games but suffered the concussion when Denver safety Kareem Jackson hit him in the head while catching a touchdown pass in Week 2. The NFL later fined Jackson $19,669 for the hit.
Thomas missed Washington's 37-3 loss to Buffalo last week. The Commanders (2-1) will need all available help against the Eagles (3-0).
"I feel good, ready to roll," Thomas said Thursday. "It was a long week last week."
Thomas has been Washington's best tight end as a combination of blocker and pass-catcher. He's adept at helping the tackles with chips, which could be a crucial element vs. the Eagles. But at 6-foot-6, 250 pounds, he's also a big target in tight situations.
"It gives the quarterback a veteran target out there," Washington coach Ron Rivera said. "They've had a good rapport through training camp, so it will be good to have him out there."
Thomas missed 11 games two years ago with a hamstring injury and then a torn ACL in his left knee. He missed four games last season because of various injuries.