Documents you need to board

More cruise vacations are ruined at the terminal check-in counter than by bad weather. Under strict maritime and border regulations, cruise lines are legally required to deny boarding to anyone whose documentation is not in 100% compliance. Requirements depend on whether your cruise is "closed-loop" or open-jaw.

Closed-loop cruises (Departing & returning to the same U.S. port)

A "closed-loop" cruise is an itinerary that departs from a U.S. port, visits contiguous territories or islands in the Western Hemisphere, and returns to the exact same U.S. port (for example, Miami to Bahamas and back to Miami, or Seattle to Alaska and back to Seattle).

Under the U.S. Western Hemisphere Travel Initiative (WHTI), U.S. citizens on closed-loop cruises may board using either:

A valid U.S. Passport Book or Passport Card; OR
An official government-issued photo ID (such as a state driver's license, REAL ID, or military ID) together with an original or certified copy of a government-issued birth certificate (issued by a state or county vital statistics office with an official seal).

Why a passport book is always strongly recommended

Even when a driver's license and certified birth certificate are legally permitted for a closed-loop sailing, we strongly recommend carrying a valid U.S. passport book.

Here is why: while you can return by sea to a U.S. port without a passport, you cannot board an international commercial flight without a valid passport book. If you fall ill and need medical evacuation, or if you miss the ship at a foreign port of call, you will be stranded abroad until you can obtain an emergency replacement passport at a U.S. Embassy.

Open-jaw and international sailings

Any itinerary that begins in one port and terminates in another (such as a one-way cruise between Seattle and Vancouver, or a Panama Canal crossing from Miami to Los Angeles) is considered an international open-jaw voyage.

A valid U.S. Passport Book is mandatory for all travelers, including infants.
Many Caribbean and Central American destinations require passports to be valid for at least six months beyond the conclusion of the trip and to contain at least two blank entry stamp pages.

Lawful permanent residents and international travelers

U.S. Lawful Permanent Residents (Green Card holders): Must present a valid, unexpired Permanent Resident Card (Form I-551) along with their national passport.
International Visitors sailing from U.S. ports: Must hold a valid national passport, any required destination visas, and an approved ESTA (Electronic System for Travel Authorization) or valid multi-entry B1/B2 tourist visa permitting re-entry into the United States.

Exact name matching

The full legal name on your cruise reservation must match the name on your government-issued travel identification letter-for-letter:

If you have recently married or changed your name, your cruise reservation name and passport must match, or you must bring an original bridging marriage certificate or legal court decree.
Do not use nicknames or abbreviations (e.g., booking as "Bob" when your legal driver's license reads "Robert").

Minor children and pregnancy restrictions

Minors traveling with only one parent or with guardians: When a child is accompanied by only one parent, grandparents, or friends, cruise lines and border agents strongly advise carrying a notarized letter of consent from the non-traveling parent(s) granting permission to leave the country and authorize medical treatment.
Pregnancy policies: Cruise lines strictly enforce a policy prohibiting any guest who will enter their 24th week of pregnancy at any point during the cruise. A physician's letter stating gestational age and fitness to travel is frequently requested at embarkation.