Yes, virtually all travelers need a valid passport to enter St. Barts (Saint Barthélemy) in 2026. As a French Overseas Collectivity, the island follows French immigration rules. For U.S., Canadian, and UK citizens, your passport must be valid for at least six months beyond your date of entry and have at least one blank page for an entry stamp. While EU citizens can technically enter with a national ID card, most international transit routes—especially those connecting through Sint Maarten (SXM)—require a passport for the transfer process. It is a high-value peer tip to know that St. Barts is not part of the Schengen Area, so even if you have a Schengen visa for mainland Europe, you may need a separate "DFA" (Department of French Americas) visa depending on your nationality. For almost every practical itinerary involving a flight or a ferry, assume the answer is a firm "yes." Always carry a digital copy of your passport as a backup, as the local authorities are strict about documentation for all visitors, including infants.