The invention relates to a method and to a device for producing cross bottom bags from tubular pieces having a selectable width Bi, comprising the steps: determination of the width Bi to be processed of the tubular pieces and provision of tubular pieces having the corresponding width, transfer of the tubular pieces to a transport apparatus, continuous and preferably uniform transport of the tubular pieces along a transport path in a transport direction (x), which runs transversely to the extension direction (z) and parallel to the width direction of the tubular pieces, the tubular pieces advantageously being transported in the horizontal position, laying of an open cross bottom, advantageously with at least one revolving tool by spreading apart the previously open ends of the tubular pieces and by aligning the corner folds formed in the process, the transfer and/or processing of the tubular pieces being varied depending on the width Bi of the tubular pieces in such a manner that the tubular pieces are arranged and/or processed on the transport apparatus with a distance from each other that is independent of the width Bi of the tubular pieces.