We say that a convex planar billiard table B is C 2 -stably expansive on a fixed open subset U of the phase space if its billiard map f B is expansive on the maximal invariant set Λ B,U = n∈Z f n B (U), and this property holds under C 2 -perturbations of the billiard table . In this note we prove for such billiards that the closure of the set of periodic points of f B in Λ B,U is uniformly hyperbolic. In addition we show that this property also holds for a generic choice among billiards which are expansive.