When flying out of LPIA, if you're U.S. bound you'll conveniently clear Customs and Immigration on the ground in Nassau. That's because LPIA is a U.S. pre-clearance facility.

Yes, U.S. citizens must go through Bahamian Customs and Immigration upon arrival in The Bahamas, and they also go through U.S. Customs and Immigration when returning. However, a unique perk for travelers to The Bahamas is the presence of U.S. Customs and Border Protection (CBP) Preclearance facilities at Lynden Pindling International Airport (NAS) in Nassau and Grand Bahama International Airport (FPO). This means that when you fly back to the United States from these airports, you clear U.S. customs before you board your plane. When you land in the U.S., your flight is treated as a domestic arrival, allowing you to bypass long lines and head straight to your next gate or baggage claim. Upon entry into The Bahamas, you are required to fill out an immigration form and make an oral baggage declaration. While U.S. citizens do not need a visa for short-term tourism, a valid U.S. Passport is mandatory for both entry into the country and re-entry into the United States.