Battlefield Hardline: Betrayal is the fourth expansion pack for Battlefield Hardline. The expansion involves the player attempting to discover who is selling them out. The expansion's content was added to the Community Test Environment for early testing on January 22, 2015 and was released on March 1, 2016 for Premium users and March 15, 2016 for non-Premium users.
The expansion includes primary weapons exclusive to the Professional kit. All players also received additional weapons for free with an update alongside the expansion. Betrayal also adds extensive customization options for player uniforms, weapons, and vehicles through the Gun Bench feature.