An expandable bag includes a body having a lower portion defining a closed bottom and a generally upstanding lower sidewall having an upper rim and an upper portion defining an upper sidewall having a lower edge coupled adjacent to the upper rim of the lower portion and having an upper rim defining a top opening. The upper portion is movable between a folded position, in which the upper sidewall is folded within the lower sidewall such that the upper rim of the upper portion and the top opening thereof is disposed generally adjacent to the upper edge of the lower portion to define an interior compartment of a certain size, and an extended position, in which the upper portion is unfolded and extended upwardly, thereby extending the height of the body and creating an interior compartment of greater size.