A lockable castor for furniture or the like includes a casing, two wheels mounted on a rotary shaft of first axis, a pivot of second axis orthogonal to the first axis, female notches in at least one of the two faces of the wheels, a lever, a male lug on the lever and complementary to the female notches, the lever being suitable for occupying two positions, a first position in which the male lug does not co-operate with any of the female notches, and a second position in which the male lug is positioned in one of the female notches, a pull connection connected to the lever, a cavity in the casing and including an opening, such that the shaft passes therethrough, the lever being constituted by a slide suitable for sliding in translation in the cavity between its two positions in a direction perpendicular to the first axis.