For US citizens, many cruises will need a valid passport book that does not expire for at least 6 months after your cruise ends. The full name matches the cruise reservation/ online check-in/ guest information form.
If you book flights with the cruise line, it is imperative that it is correct to avoid any name change fee/ cancellation and book at current rates.
For closed-looped US sailings, you do not need to have a passport book but recommended. You can bring your certified birth certificate and driver's license. Keep in mind that if you use this form of documentation, you cannot fly home in case of an emergency- Caribbean, Mexico, or Canada. Airlines will require a passport book not a passport card to fly from an international city back to the US. NOTE: The White Pass train ride in Skagway takes you to the Yukon (Canadian territory), you will need to supply a passport to enjoy the excursion.
Passports can take up to two months to process, so it is imperative to check on your passport expiration date when you do book a cruise. It does last every 10 years for adults and 5 years for children.
US Department of State- DS-11 Form
Need visas, try CIBT Visa which the cruise line use or add it to your reservation when you book the cruise.
Without proper documentation, the cruise line may be denied boarding WITHOUT any refunds. Insurance may or may not cover you.