Abstract: A waistband stay for clothing inserts removably into the waistband of a pair of trousers, a dress or skirt, a pair of shorts, etc., and stiffens the waistband thereacross. This serves to prevent circumferential gathering, wrinkling, and the like of the waistband along the front and sides thereof due to compression of the fabric across the stomach or midriff of a person as the person sits, stoops, or otherwise bends forward at the waist. The present waistband stay is preferably formed of an elongate, narrow, thin piece of semi-flexible plastic which provides sufficient stiffness across its width to preclude folding of the waistband when installed therein. The use of the present waistband stay ensures that the waistband of the garment will remain unwrinkled and will provide a smooth and finished appearance for the article of clothing and for the wearer throughout the day.