Do you need a Pass Port?

Yes and no. According to Carnival, you do not need a pass port as long as you are leaving on a cruise ship from and returning to that same USA port. Now, pass ports are highly recommended, but not required. The only draw back to not having a pass port is, if you needed to cut your cruise short and fly back to the USA from a non-USA state or territory, you would have to have a pass port to enter the USA.