Begin by going to Charters / Day Trips located within the Scuba Diving feature on the tree menu. Charters are not automatically moved over to the Historical Excursion view. This allows for payments to be made after the charter has ended.

To close a charter you must first click the Enter Edit Mode icon in the toolbar. This will make the charter selected in the Charters / Day Trips window editable. The Close Trip column is the very last column, which you can get to by using the scroll bar at the bottom of the window.

Select the charter you want to close and check the Close Trip box. Click the Save icon in the toolbar to commit the change and then click the Leave Edit Mode icon in the toolbar. The closed charter will be in the Historical Charters view, accessed by clicking that icon in the toolbar. (The current charters list will not be refreshed until you move off of it by going to Historical Charters or the next time you open the Current Charters list view).