Many ships, including cruise liners have omitted having a 13th deck due to triskaidekaphobia. Instead, the decks are numbered up to 12 and skip straight to number 14. Hotels, buildings and elevator manufacturers have also avoided using the number 13 for rooms and floors based on triskaidekaphobia.

Many cruise ships and high-rise buildings skip "Deck 13" primarily due to triskaidekaphobia, the deep-seated cultural superstition that the number 13 is unlucky. This fear is rooted in various historical and religious traditions, most notably the "Last Supper" where Judas, the 13th guest, betrayed Jesus. In Norse mythology, the god Loki was also the 13th guest at a feast that led to a tragedy. In the maritime world, which is traditionally highly superstitious, the fear is amplified; many believe that assigning a deck or cabin the number 13 is "summoning misfortune" or tempting fate. By skipping from Deck 12 directly to Deck 14, cruise lines like Royal Caribbean, P&O, and Carnival avoid making nervous guests uncomfortable. Interestingly, some ships do have a Deck 13 but use it for non-residential purposes, such as sports courts, sun decks, or crew quarters, where guests are less likely to feel "cursed" by their sleeping arrangements. In some cultures, other numbers are skipped instead; for example, Italian cruise lines like Costa sometimes skip Deck 17 because 17 (XVII) is an anagram for "VIXI," which in Latin means "I have lived" (implying death).