(SAN JUAN, PUERTO RICO) — Princess Cruises requires passport books for all sailings beginning in San Juan, Puerto Rico, a policy that sets a firmer document rule for Southern Caribbean trips from the island than for some other Caribbean roundtrips from U.S. ports.

The cruise line also requires a passport for all voyages that call at Martinique or Guadeloupe, extending the rule beyond Puerto Rico departures and affecting itineraries that touch those French Caribbean islands.

Princess says it “highly recommends” a passport for every guest. U.S. State Department guidance also says cruise lines may require a passport even when the government does not.

That distinction leaves some travelers with two separate standards to check before departure: government entry rules and the cruise line’s own boarding requirements. On Princess Cruises, the company rule controls whether a passenger can board.

On Southern Caribbean routes, the clearest line falls at Puerto Rico. Sailings that start in San Juan require a passport, making passport books mandatory for travelers who begin their trip there.

Barbados sits in a different category. Princess’s passport policy page does not list Barbados as a blanket passport-only departure point, but the document rule still turns on the itinerary’s ports and on whether the trip includes international air travel or non-WHTI-compliant segments.

Martinique and Guadeloupe create another fixed point in the policy. If a voyage calls at either island, Princess requires a passport regardless of the departure port.

That matters on Southern Caribbean schedules, where port combinations can shift the document requirements even when cruises appear similar on the surface. A sailing from Barbados and a sailing from Puerto Rico may visit overlapping islands, but a call at Martinique or Guadeloupe changes the paperwork standard.

Princess still accepts certain WHTI-compliant alternatives for many other Caribbean roundtrips from U.S. ports for U.S. and Canadian citizens and nationals. Those alternatives do not erase the stricter rule for San Juan departures or the separate passport requirement tied to Martinique and Guadeloupe.

WHTI refers to the Western Hemisphere Travel Initiative rules that allow some U.S. and Canadian travelers on closed-loop cruises to use documents other than a passport book. Those alternatives are identified only in general terms, while stressing that they apply to many other Caribbean roundtrips from U.S. ports, not across the board.

Closed-loop itineraries are at the center of that difference. On some Caribbean sailings that begin and end in the same U.S. port and stay within WHTI-eligible destinations, a passport book is not always required for U.S. and Canadian citizens and nationals.

Princess nonetheless urges passengers to carry one. The company’s recommendation grows more practical on itineraries that involve multiple jurisdictions, changing port calls, or air connections outside the continental United States.

Validity rules add another layer. Princess says passports must be valid for at least six months after the last day of travel.

That requirement reaches beyond simply having a passport in hand. A traveler with a document that expires too soon can run into the same boarding problem as someone who arrives without the required book.

Air travel can also settle the question quickly. If a cruise involves international air travel, or if a passenger needs to fly home unexpectedly, a passport book is required.

The practical consequence is broader than the embarkation day check at the terminal. A passenger who starts a vacation expecting to sail roundtrip may still need to leave by air after a medical issue, a missed ship connection, or another disruption, and Princess points travelers toward carrying a passport book for that reason.

San Juan departures bring that issue into sharper focus because the port itself already falls under Princess’s mandatory passport rule. Travelers booking Southern Caribbean cruises from Puerto Rico now face a more straightforward test: bring a passport book, and make sure it remains valid for at least six months after the last day of travel.

Barbados departures require more itinerary-by-itinerary review. The absence of a blanket passport-only rule for Barbados does not mean every sailing from the island can be boarded without a passport book, because the ports visited and the travel segments still decide the document standard.

That leaves Martinique and Guadeloupe as two of the most important names on any route plan. Their inclusion triggers a passport requirement whether the voyage starts in Puerto Rico, Barbados, or another port.

Princess Cruises’ policy also shows how cruise documentation rules can run ahead of what some passengers expect from government travel guidance alone. The U.S. State Department says cruise lines may require a passport even when the government does not, and Princess has done that in several parts of its Caribbean operation.

The result is a reshaped planning process for Southern Caribbean travel from Puerto Rico and Barbados. Travelers comparing fares, cabin categories, and embarkation ports now also have to compare document rules route by route, with San Juan departures, Martinique calls, Guadeloupe calls, and any international air travel all pushing the answer toward the same document: a valid passport book.

For cruise buyers weighing flexibility, the policy favors carrying more documentation rather than less. Princess still allows some WHTI-compliant alternatives on certain U.S. port roundtrips, but its own guidance points in one direction for Southern Caribbean itineraries that begin in Puerto Rico, touch Martinique or Guadeloupe, or include an international flight segment.

In practice, the closest thing to a bright-line rule is also the simplest one. On Princess Cruises, passengers sailing from San Juan, calling at Martinique or Guadeloupe, or taking international air connections need passport books, and those books must remain valid for at least six months after the last day of travel.