If you cancel the excursion at least 3 days prior to the
start of the cruise, there is no penalty. After that time you will be charged for the excursion. However, if, once onboard, you wish to cancel you can go to the Port Adventures desk and tell them you want to cancel. If there's a wait list for that excursion, and
DCL can "resell" your spot, then you will not be charged. If there's no wait list, you will be charged.