In a closure plate for a slide closure on the spout of a container containing molten metal, two outer longitudinal sides, a flow-through opening disposed on a central longitudinal axis of the closure plate and a closing surface passing from the latter are provided. There are formed on each of these two outer longitudinal sides, at least two shoulder surfaces serving as clamping surfaces or as centring surfaces of the closure plate which are at an angle to the longitudinal axis and tapering inward. At least on the shoulder surfaces on the side of the closing surface, adjoining outer sides are provided which are respectively at a smaller angle to the longitudinal axis than those of the shoulder surfaces.