Why is Friday the 13th unlucky? Myths, superstitions and stories behind jinxed day

In western superstition, the day is considered the unluckiest of the year, with its roots found in Norse mythology and Jesus's last supper

The fear of Friday the 13th is called paraskevidekatriaphobia. Photo: Olivier Le Moal
Beta V.1.0 - Powered by automated translation

The idea that Friday the 13th is unlucky is as familiar in western superstition as not walking under ladders, being wary of black cats crossing your path and breaking a mirror.

Occurring on any month when the first day begins on a Sunday, Friday the 13th comes around at least once a year — as it will in 2022 — but can happen up to three times a year.

Why is a Friday unlucky?

The association between the number 13 and bad luck has a long history with roots in Norse mythology, Christianity and Greek gods. Its connection to Friday, however, has more opaque origins.

Although historians are generally agreed that the link between Friday and the number 13 wasn’t really established until the 19th century, one particular Friday the 13th in the 1300s remains famous as the beginning of the end of the Knights Templar.

After centuries of building power and wealth, the downfall of the European monastic military order began in the early morning hours of Friday, October 13, 1307, with a series of arrests, which would go on to spell their end.

In Britain, Friday used to be known as “Hangman’s Day” as that was the day those who had been condemned to death would be sent to the gallows.

Cementing the day as an unlucky one was a novel by American businessman TW Lawson, titled Friday, the Thirteenth, in which a broker capitalises on superstition to start a panic on Wall Street on Friday the 13th.

The fear of Friday the 13th is called paraskevidekatriaphobia.

Why is the number 13 unlucky?

'The Last Supper' by Leonardo da Vinci shows there were 13 people at dinner, including the traitorous Judas Iscariot. Photo: Wikimedia Commons

Many cultures have superstitions centred around the number 13.

According to folklore, the number gained its unlucky connotations in Norse mythology, owing to a story about 12 gods at a dinner party in Valhalla. Uninvited, Loki showed up as the 13th guest and persuaded Hoor, the blind son of Odin, to shoot Balder, another of Odin’s sons with a mistletoe-tipped arrow. Balder died, and the tragedy was associated with the number 13.

In Christianity, there were 13 disciples at Jesus Christ's Last Supper on Maundy Thursday, the night before his crucifixion. Judas Iscariot, the disciple who would betray Jesus, was the 13th man to take his seat.

Nods to the superstition can be found in modern culture, with many buildings omitting a 13th floor, going from 12 straight to 14, while some airlines do not have a row 13.

Tuesday the 13th, and Friday the 17th are unlucky too

In Hispanic and Greek culture, Tuesday the 13th is traditionally considered an unlucky day and is known as martes trece. In Greece, Tuesday is the day associated with Ares the god of war, and Constantinople, as it was then-called, fell twice on a Tuesday: in 1204 during the Fourth Crusade, and in 1453 to the Ottomans.

In Italy, the number 13 is actually considered lucky, and Friday the 17th is the unlucky day. Alitalia, the country's airline, does not feature row 17 on its planes.

The connection between the number 17 and bad luck is owing to the Roman numerals for 17, XVII, which when rearranged create the word VIXI. The word translates as “I have lived”, the past tense of which implies death.

Updated: May 13, 2022, 9:09 AM