The team was managed by former MLS player Peter Nowak, in his second season with the club.

During the off-season, the team lost Fred, Seitz, Salinas, and Moreno through re-entry and expansion drafts.

[4] During the Supplemental Draft, the Union picked up another 3 players: Ryan Richter (MF/F), Josh Walburn (D) and Matt Marcin (MF).

[6] Toward the end of January, Philadelphia released their other goalie from the 2010 season, Brad Knighton.

[7] On January 20, Philadelphia introduced two new players: Colombians Faryd Mondragón (GK) and Carlos Valdés (D).

[9][10] Bimbo Bakeries has sponsored other teams in Mexico and Costa Rica, but this is their first time in MLS.

Philadelphia Union will play their first pre-season game against the U-17 US Men National Team on February 6.

[11] The club announced the signing of former MLS Most Valuable Player Carlos Ruiz on February 22.

[13] Note: Flags indicate national team as defined under FIFA eligibility rules; some limited exceptions apply.

Each club in Major League Soccer is allocated 8 international roster spots, which can be traded.