Few dates stir up collective superstition quite like Friday the 13th. For some, it’s just another date on the calendar. For others, it’s a cosmic red flag — a date to avoid big plans, dodge black cats, and sleep with a protective crystal under the pillow.

But where does this reputation come from? And why do we assign so much symbolic weight to one simple pairing of a number and a day? The answer weaves through ancient beliefs, biblical betrayals, and modern horror films. Here’s everything you need to know about this infamously eerie date.

Why is Friday the 13th considered unlucky?

The superstition around Friday the 13th isn’t rooted in a single origin story — rather, it’s the convergence of two long-standing symbols of misfortune: the number 13 and the day Friday.

In many Western cultures, the number 13 has been seen as problematic for centuries. It disrupts the perceived perfection of 12 — twelve months, twelve zodiac signs, twelve apostles. That "extra" guest at The Last Supper, for example, was Judas Iscariot, the 13th attendee who would go on to betray Jesus.

Friday, too, has carried its own reputation. It’s said to be the day of the crucifixion, and historically it was viewed as an inauspicious day for starting journeys, signing contracts, or holding weddings.

Together, these two taboos collided in the 19th century, and by the early 20th century, Friday the 13th had become a widely accepted harbinger of bad luck. One theory even links the superstition to Friday, October 13, 1307, when the Knights Templar were arrested across France — a brutal purge that only added fuel to the idea of the date being cursed.

Fast forward to 1980, and the horror film Friday the 13th was released, unleashing Jason Voorhees, one of the most recognisable figures in the genre. Although he didn't don his iconic mask until later in the film's franchise, Jason became a pop culture symbol of lurking dread and mindless violence, cementing the date’s eerie reputation in the public consciousness.

How often does Friday the 13th occur?

Friday the 13th occurs at least once a year, and sometimes up to three times. It happens when the 13th day of the month lands on a Friday — something determined entirely by the calendar, not by fate.

In 2025, there will be one Friday the 13th, which falls today, on June 13, 2025 .

Because of the way months are arranged and leap years work, Friday the 13th is more likely to occur in February, March, or November. Years that begin on a Sunday are especially likely to host multiple Friday the 13ths.

But the date’s recurrence only seems to deepen its mystique — a quiet reminder that the so-called “unlucky” can show up in everyday places, quietly threaded into time itself.

The most common Friday the 13th superstitions

While most Friday the 13ths pass without incident, the day is still treated cautiously by many.  In fact, there's even a word for the fear of Friday the 13th: paraskevidekatriaphobia. Some popular superstitions associated with Friday the 13th include:

• Avoiding black cats
• Postponing major life events
• Not walking under ladders
• Not starting new projects
• Wearing protective crystals or talismans

Want to commemorate the date? Why not mark Friday the 13th by delving into our pick of the best horror films of all time.

Feature image via Pinterest.