Thurmond confirmed the news in a text message to the Philadelphia Daily News after ESPN NFL Insider Adam Schefter reported earlier in the day that Thurmond was hanging up his cleats for good.
Thurmond has told people close to him that he doesn't want to play football any longer and he wants to pursue other opportunities, the source told Schefter.
Thurmond has been on three teams in the past three seasons and has played three positions: cornerback, slot corner and safety.
The Eagles signed Thurmond to a one-year, $3.25 million contract last year with the expectation that he would compete for a cornerback job. After the draft didn't produce a replacement for departed free agent Nate Allen, the coaches asked Thurmond if he would move to safety.
Thurmond wound up starting all 16 games, a first for him in his sixth NFL season. He intercepted three passes, forced two fumbles and recovered one, returning it for a touchdown.
The Eagles credited Thurmond with 62 tackles, including six for loss. He also had two sacks.
Thurmond was primarily a slot cornerback with the Seattle Seahawks in 2013, earning a Super Bowl ring with the team that drafted him out of Oregon in the fourth round of the 2010 draft.
In 2014, Thurmond signed a one-year contract with the New York Giants. In his second game, he tore a pectoral muscle and was placed on injured reserve.
Thurmond said after the 2015 season that he expected to leave Philadelphia and thought he'd have more opportunities at cornerback.
ESPN Eagles reporter Phil Sheridan contributed to this report.