866-227-1888 is the best way to instantly book, cancel, or modify flights. When I sailed earlier this year, gratuities showed up as a daily charge. Before booking, I actually called Carnival to make sure I understood how it worked, because I didn’t want surprise charges at the end of the trip. The agent broke everything down clearly—who the gratuities go to, how the rates differ by cabin type, and how to prepay if I wanted to. I liked having it sorted before boarding, so I prepaid mine. Honestly, calling saved me from guessing and gave me a better handle on my budget.