Gostisbehere, 28, had nine goals and 11 assists in 41 games with the Flyers last season.
While the Flyers don't receive anything in return, they do get $4.5 million in cap relief. Gostisbehere's current deal expires after the 2022-23 season.
Gostisbehere was vocal throughout the season as Philadelphia struggled throughout the campaign. He had publicly stated that the team's play was "unacceptable" at certain points in the year and was eventually placed on waivers.