TY - JOUR AB - Purpose The increase of containership sizes driven by the need to create greater economies of scale seems to be an endless process. Vessels of more than 21,000 TEU are presently on order. The purpose of this paper is to question whether a positive effect still remains at present mega ship sizes and, even if this was the case, whether such presumably small effect would be outweighed by costly operational impacts for the lines and the ports out of the huge ship sizes.Design/methodology/approach The effect of increasing ship sizes on the three major cost items in container shipping have been investigated by extrapolating founded regression curves, applying respective physical laws and referring lumpsum crewing cost (as the major part of the vessel’s running costs) to various ship sizes.Findings In this paper, it is shown that further effects of lower slot costs lessen while ships get larger. Hence, a further increase in ship sizes would not significantly reduce transport costs anymore. In contrast, the necessary efforts to prepare the ports for ships of ever-increasing size are growing over proportionally with every additional metre of draught and/or beam. It is shown that an ongoing increase of containership sizes, e.g. in the Europe-Far East trade, does not bring any further benefit, neither for the ports and their terminals nor even for the lines itself and not even for the shippers! It is an amazing mechanism that all stakeholders act rationally on their own, but the overall effect for all of them (including the public) has turned into negative.Originality/value The results may pave the way for a closer cooperation among ports, e.g. within the Hamburg-Le Havre range. Ports and terminals may see the opportunity to escape the spiral of ongoing efforts for deepening and widening the fairways and installing ever-bigger gantry cranes by agreeing on a joint policy with regard to maximum ship size. VL - 2 IS - 3 SN - 2397-3757 DO - 10.1108/MABR-01-2017-0001 UR - https://doi.org/10.1108/MABR-01-2017-0001 AU - Malchow Ulrich PY - 2017 Y1 - 2017/01/01 TI - Growth in containership sizes to be stopped? T2 - Maritime Business Review PB - Emerald Publishing Limited SP - 199 EP - 210 Y2 - 2024/04/24 ER -