A source said the Eagles are giving McCown a one-year deal that includes $2 million fully guaranteed and could be worth up to $5.4 million.
McCown, 40, was planning to be an ESPN analyst this season but had wanted to play and told the network that if the right opportunity came along, he would strongly consider it. Now it has.
He plans to resume his broadcasting career with ESPN after the season, a source said.
"Just organizationally, from the top-down, starting obviously with [owner] Mr. [Jeffery] Lurie and [general manager] Howie Roseman and [coach] Doug Pederson and just what they've built here. Throughout my career for the most part it's been in kind of start-up type situations where there's a new head coach or they're rebuilding, and that's kind of been my job to go in and kind of help with that type of stuff," McCown said Sunday.
"So to have an opportunity to kind of come to a place where they've had success obviously, recent success, and win a championship, and be a part of that, it was hard to stay away from."
The Eagles have lost two quarterbacks this preseason -- Cody Kessler to a concussion this week and Nate Sudfeld to a broken bone on his left wrist last week -- but Philadelphia was interested in McCown even before then.
McCown was coaching his two sons (ninth- and 10th-graders) at Myers Park High School in Charlotte, North Carolina. Asked Sunday what kind of shape he is in, McCown said, "we'll find out."
"No, I feel good. I was running, coaching high school football, on the field and playing hoops and trying to stay active," he said. "I'm not really somebody who likes to sit still. Hopefully that won't be too big of a transition. Obviously, playing professional football is different and I wasn't necessarily training for that, but at the same time, still pretty active, so it shouldn't be a problem."
Philadelphia will be McCown's 11th NFL team and first NFC East team. He spent the past two seasons with the New York Jets, going 5-11 as a starter while throwing 19 touchdowns and 13 interceptions overall.
The Eagles expect Sudfeld, who received a second-round tender during the offseason, to return this season.
The well-traveled McCown is one of seven players in NFL history to attempt a pass for seven different teams. He and Ryan Fitzpatrick of the Miami Dolphins are the only active players on the list, and each has the opportunity this season to be the first QB to throw a pass for eight different teams.
ESPN's Tim McManus contributed to this report.
Tannenbaum: Hoyer could be viable option for Eagles
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