Why are certain room numbers sometimes missing in hotels?

You press 12 in the elevator and notice: after 12 comes 14. Or you walk down the hallway and find rooms 308 and 309—and then suddenly 311. Room 310 simply doesn’t exist.

A planning error? No. It’s intentional. And the reasons behind it run deeper than you might first think.

The number 13 and its long history

In much of the Western world, 13 is considered an unlucky number. This belief has its roots in Christianity (the 13 people at the Last Supper), Norse mythology, and all sorts of other cultural sources that have built upon one another over the centuries. Today, the clinical manifestation of this fear is even called triskaidekaphobia—and there are indeed people who would avoid rooms or floors numbered 13.

Hotels, which compete daily for bookings, have done a simple calculation: a room that some guests are reluctant to occupy is not economically viable to label as such. So the 13th floor becomes the 14th—or room 13 becomes 12A. The physical room still exists; it’s just been given a different name.

Elsewhere, it’s the number 4

In China, Japan, and Korea, it’s not so much the number 13 as the number 4 that’s considered unlucky. In Chinese, the pronunciation of “four” sounds very similar to the word for “death”—an unpleasant sound that many prefer to avoid. The result: In hotels in these countries, the room number sequence may have gaps that initially confuse a Western guest. Sometimes not only room 4 is missing, but also 14, 24, 34—and entire floors containing the number four.

International hotel chains that operate in many countries simultaneously have to keep all of this in mind. Some solve it pragmatically: they simply omit all culturally problematic numbers and get by that way all over the world.

Psychology is cheaper than empty rooms

Behind the whole matter lies a fundamental insight of hotel management: a guest who feels uncomfortable writes a worse review, is less likely to book again, and does not recommend the hotel to others. These costs are difficult to measure, but they are real. A missing room number, on the other hand, costs practically nothing—except perhaps a bit of confusion among guests who wonder why the door won’t open.

So the next time you stay at a hotel, it’s worth taking a brief look at the numbers in the hallway. Maybe there’s more missing than you’d expect.