Most cruise lines don't offer roundtrip Hawaii sailings. This is because foreign-flagged cruise ships sailing between U.S. destinations need to include a foreign port in their itineraries to comply with passenger shipping laws.

The primary reason many major cruise lines do not offer "inter-island" Hawaii cruises is a 19th-century maritime law called the Passenger Vessel Services Act (PVSA) of 1886. This protectionist law mandates that any ship transporting passengers between two U.S. ports must be U.S.-built, U.S.-owned, and U.S.-crewed. Since almost all modern mega-cruise ships are built in Europe and flagged in foreign countries (like the Bahamas or Panama), they cannot legally pick up passengers in Honolulu and drop them off in Maui without first visiting a "distant foreign port" (like Fanning Island or Ensenada, Mexico). This requirement adds several days of travel across the open Pacific, making short 7-day Hawaiian itineraries logistically difficult. Currently, only Norwegian Cruise Line’s Pride of America operates year-round inter-island cruises because it was granted a specific exemption to fly the U.S. flag. For other lines, Hawaii remains a seasonal destination reached via long trans-Pacific crossings from the West Coast or as part of "world cruise" segments.