Yes, in many cases, someone can take your place on a cruise through a passenger substitution or "name change," but the rules are quite specific. Most major cruise lines (like Royal Caribbean, Carnival, and NCL) allow you to replace one guest in a cabin with a new person, provided that at least one original passenger remains on the reservation. You cannot typically "sell" or transfer the entire booking to a completely new group of people. There is usually a name change fee, which can range from $50 to $150 per person, depending on how close you are to the sailing date. Once you are within the "final document" phase (usually 72 hours to 7 days before departure), name changes are often blocked entirely due to manifest requirements and port security regulations. If you booked a "non-refundable" or highly promotional fare, substitutions might be prohibited. It is essential to ensure the new guest meets all age, visa, and vaccination requirements for the specific itinerary, as the cruise line will treat them as a brand-new passenger for all legal and documentation purposes.