A highchair includes a seat assembly, a tray connected with the seat assembly, a leg assembly connected with the seat assembly, and an adjustment mechanism. The seat assembly includes a rear support surface and a lower support surface for supporting an infant or child. The leg assembly is configured to support the seat assembly above a floor surface. The adjustment mechanism can be for adjusting the tray with respect to the seat assembly or the seat assembly with respect to the leg assembly. The adjustment mechanism can include a button, a linkage, a cable, and a locking member.