RECLINER

A recliner according to one aspect of the present disclosure includes a plate-shaped ratchet, at least one pawl, a plate-shaped guide member, and a ratchet seating portion. The ratchet seating portion is provided on the guide member to be positioned on an inner peripheral side of a second flange and between two guide walls adjacent to each other in a circumferential direction on the guide member. The ratchet seating portion protrudes toward the first flange of the ratchet and is configured to come into sliding contact with a tip of the first flange.