Abstract: A bottom closure for a beverage container sleeve is made of a soft, flexible polyvinyl chloride and has a short cylindrical sidewall dimensioned to receive the end of an insulating sleeve. The bottom edge of the sidewall is continuously connected to the outer periphery of an annular bottom ring which has a width significantly greater than the radial thickness of the sleeve. A central bottom disk is connected to the inner periphery of the annular ring by a sloping wall, the central disk having openings there through to prevent the formation of an over or under pressure condition within the sleeve when a beverage container is inserted into or extracted therefrom.