A selectable one-way clutch includes: a pocket plate including pockets provided along a circumferential direction on one surface; a notch plate that is rotatable with respect to the pocket plate, the notch plate including notches provided along a circumferential direction on a surface facing the one surface; struts that are plate-shaped and housed in the respective pockets; and a selector plate disposed between the pocket plate and the notch plate, and configured to switch, by rotating coaxially with the pocket plate, between: a state in which the struts have risen toward the notch plate; and a state in which the struts are housed in the respective pockets. The notch plate includes flat portions between the notches that are adjacent in the circumferential direction, and each flat portion includes a first recess at a position where the corresponding strut having risen toward the notch plate is brought into contact.