The NFL's new league year begins on Wednesday, March 16. That's when all players with expiring contracts officially become free agents and can sign with other clubs.

Teams can begin contacting agents of those players on Monday, March 14, but cannot speak to the player, nor sign a contract until the new league year begins.
For the Bills, 15 players are scheduled to become unrestricted free agents (UFAs), free to sign with other clubs, including defensive tackle Harrison Phillips, cornerback Levi Wallace, wide receiver Isaiah McKenzie, and defensive back and special teams standout Siran Neal.
Two players are scheduled to become restricted free agents (RFAs), offensive lineman Ryan Bates and defensive tackle Justin Zimmer. The Bills will have an opportunity to match any offer another teams gives them, or receive possible compensation for them leaving, if they give those players certain levels of contract offers. Those specific amounts for this offseason have yet to be determined by the league.
One player, linebacker Tyrel Dodson, is an exclusive rights free agent (ERFA). As long as the Bills give him an offer for the minimum salary, they will retain Dodson's rights.

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