Abstract: A reusable insulating jacket for beverage containers includes a housing having a cylindrical side wall of flexible insulating material defining an internal cavity for receiving a beverage container. An elongated slit is formed in the side wall which extends the entire height of the side wall and is defined between edges of the side wall. An elongated, openable fastener, such as a zipper, is attached to the side wall edges for selectively opening and closing the slit to facilitate insertion and removal of a beverage container from the cavity in the side wall.