An adjustable armrest mechanism includes a mounting bracket securely mounted relative to a vehicle seatback, an armrest rotatable relative to the mounting bracket, an armrest bracket securably attachable to the armrest, a pawl attachable with the armrest bracket, a coil spring for biasing the pawl, and a ratchet securably mounted onto the mounting bracket. The ratchet includes a camming surface having a plurality of serrated teeth for engagement with the pawl. A plurality of in-use positions are defined by engagement between the pawl and the serrated teeth. The armrest bracket includes a stop which prevents further rotation of the pawl member during disengagement. Cooperative engagement of the pawl with an armrest stop and a ratchet stop on the camming surface prevents further rotation of the pawl during relative rotation into the non-use position.