Number 4 is unlucky, 7 is lucky

The number 4 is avoided where possible (it's a homophone for "death"), so don't be surprised by missing 4th floors or hesitation around groupings of four.

Korea SocialcasualUpdated September 2, 2026

Don’t be surprised if an elevator panel skips straight from 3 to 5, or labels the fourth floor “F” — it’s a deliberate substitution, not a building error.

When you have a free choice in how many of something to buy, arrange, or group (gift quantities, place settings, matching items), odd numbers like 3, 5, or especially 7 read as neutral-to-lucky, while 4 is worth avoiding if it costs nothing to do so.

This is a mild, background-level superstition, not an enforced rule — nobody will call you out for it, and plenty of modern Koreans don’t think about it day to day.
It compounds with the gift-giving taboo — see the note on avoiding sets of four as gifts specifically, where the superstition carries more social weight than it does elsewhere.

Why it matters

In Sino-Korean, 4 (사, sa) sounds identical to the character for death, the same logic that makes 13 unlucky in the West. It shows up in small, visible ways: some buildings label the fourth floor "F" instead of "4" on elevator panels, and people may unconsciously avoid picking a fourth item, seat, or grouping when there's a choice. It's a soft superstition rather than a hard rule most people actively enforce, but it explains oddities you'll notice once you know to look for them.

Number 4 is unlucky, 7 is lucky

Why it matters

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