Gather your paperwork from the cruise line or travel agent together. If you bought Trip Cancellation Insurance (TCI), be sure to have that paperwork handy.
Thoroughly read over the paperwork so you know what your refund options are. The amount of your refund will often depend on how far away the sailing date is, among other factors.
Phone the cruise line or the travel agent direct. Since this is a time-sensitive matter, don't e-mail or fax your cancellation.
Once you reach the appropriate party, explain your circumstances to the company representative. They'll want to know the reason you are canceling your cruise.
Follow the directions on the details of how to cancel your cruise from the company representative. You should receive a confirmation right then or within a few days.