A cage segment for a bearing rotatable around an axis being able to receive a plurality of rolling elements configured to travel on two annular raceways respectively on inner and outer rings of the bearing, and including an inner wall that extends circumferentially in the form of a cylinder, the axis of symmetry being the axis (X1), an outer wall that extends circumferentially in the form of a cylinder, the axis of symmetry being the axis (X1), two end portions that are circumferentially opposed, which extend radially with respect to the axis (X1) and which connect together the inner wall and the outer wall, a plurality of successive pockets for receiving the rolling elements, so that two successive pockets are circumferentially delimitated by a radial beam, The radial beam extending radially with respect to the axis (X1), the radial beam comprising two end portions so that one end portion connects with the inner wall and the other end portion connects with the outer wall, The radial beam provides a first recess that extends axially with respect to the axis (X1).