No, you generally cannot take a boat from Miami to The Bahamas without a valid U.S. passport. While the Bahamas is close to Florida, it is a sovereign nation with its own immigration laws. All travelers entering the Bahamas by private vessel or commercial ferry must clear customs and immigration at an official Port of Entry, and Bahamian law requires U.S. citizens to present a valid passport for entry. There is a common misconception involving "closed-loop" cruises (voyages that begin and end at the same U.S. port), which sometimes allow U.S. citizens to travel with just a birth certificate and a government-issued ID. However, even on these cruises, both the U.S. State Department and the Bahamian government strongly recommend a passport. If you are on a private boat and have a medical emergency or a mechanical breakdown that requires you to fly back to the U.S. from the Bahamas, you will be strictly prohibited from boarding an international flight without a passport. As of 2026, security protocols are even tighter, and a valid passport remains the only document that guarantees you can enter the Bahamas by sea and legally return to the United States by any means.