Abstract: An adjustable card box to hold a multiplicity of the slide-type bingo cards in an upright viewing position and in a manner such that they can be rapidly flipped through comprises two trays, one of which fits and telescopes within the other. A finger-operable locking means serves to lock the position of one tray with respect to the other to permit expanding and collapsing of the space encompassed by the trays to facilitate storage of the box and to permit a player to accommodate the number of cards he wishes to play. The card box has front and rear upward extending flaps pivotedly mounted to the sidewalls, which in the open position serve to support the cards in the viewing position. The flaps can be folded down into the box flat to permit storage of the box and carrying of a vertical stack of playing cards on the box.