The trade is not yet official, but the expectation is but Flames forward Ales Kotalik is part of the deal too.
Regehr finished with 17 points and a plus-2 rating in 79 games this season. Kotalik, 32, spent last season between Calgary and the Flames' AHL affiliate Abbotsford. He finished with six points in 26 games for Calgary.
At first, Regehr turned down waiving his no-move clause to accept a trade to Buffalo. Sabres owner Terry Pegula was reportedly influential in Regehr's eventual decision.