Demurrage is a charge for exceeding the allotted lay days that a ship is allowed to stay at a port or terminal for loading or unloading cargo. In other words, if a ship stays longer than the agreed-upon time period, demurrage charges will be imposed on the cargo owner or shipper for the additional time used. The purpose of demurrage charges is to compensate the shipping company for the delay in the release of its equipment and to encourage quick turnaround times at ports or terminals.