A snap cage for a ball bearing assembly, which comprises: an annular body having one side face opened at a plurality of circumferential locations to define respective pockets each for retaining a ball and having an inner face; recessed areas defined in the inner face of the respective pocket so as to extend from a pocket open edge on a cage inner diametric side towards a cage outer diametric side; and a pair of pawls opposed to each other in a circumferential direction, the pair of pawls being provided on the open side of the pocket so as to protrude in an axial direction; in which the distance between respective tip portions of the pair of the pawls in the pocket on the cage outer diametric side is smaller than the distance between the tip portions of the pair of the pawls in the pocket on the cage inner diametric side, or in which respective tip portions of the pair of pawls in the pocket on the cage inner diametric side are spaced a distance from each other, but respective tip portions of the pair of pawls in the pocket on the cage outer diametric side are connected together, and wherein the recessed areas are provided at a plurality of locations while positioned on respective sides of a center of the pocket in a cage circumferential direction at the open edge of each of the pockets characterized in that the inner face of each of the recessed areas is of a substantially cylindrical surface shape following a surface of the imaginary cylinder having its center lying in a direction radially of the cage and is of such a shape that each of the recessed areas extends from the open edge on the cage inner diametric side towards a pitch circle of arrangement of a row of the balls and has a width gradually getting shallow and narrow from a cage inner diametric edge to the pitch circle of the row of the balls. an annular body having one side face opened at a plurality of circumferential locations to define respective pockets each for retaining a ball and having an inner face; recessed areas defined in the inner face of the respective pocket so as to extend from a pocket open edge on a cage inner diametric side towards a cage outer diametric side; and a pair of pawls opposed to each other in a circumferential direction, the pair of pawls being provided on the open side of the pocket so as to protrude in an axial direction; in which the distance between respective tip portions of the pair of the pawls in the pocket on the cage outer diametric side is smaller than the distance between the tip portions of the pair of the pawls in the pocket on the cage inner diametric side, or in which respective tip portions of the pair of pawls in the pocket on the cage inner diametric side are spaced a distance from each other, but respective tip portions of the pair of pawls in the pocket on the cage outer diametric side are connected together, and wherein the recessed areas are provided at a plurality of locations while positioned on respective sides of a center of the pocket in a cage circumferential direction at the open edge of each of the pockets characterized in that the inner face of each of the recessed areas is of a substantially cylindrical surface shape following a surface of the imaginary cylinder having its center lying in a direction radially of the cage and is of such a shape that each of the recessed areas extends from the open edge on the cage inner diametric side towards a pitch circle of arrangement of a row of the balls and has a width gradually getting shallow and narrow from a cage inner diametric edge to the pitch circle of the row of the balls.