Abstract: The fastener for waistbands on trousers or skirts has a detent rail fastened to one part of the waistband and a slide displaceable on the rail. The slide carries a pivotal lever which extends beyond its pivot axis into a detent projection. The slide or the lever is detachably connectable to the other part of the waistband. The other waistband part is provided on its inside with a hook which is engageable with an opening in either the slide or the lever. The opening is coordinated with a slide surface that facilitates this engagement even without looking. In this respect the slide surface is the outside surface of the lever, and it is located ahead of, with respect to the engagement direction, and lower than the opening.