In 2026, Friday the 13th Has an Evil Twin

A Lucky Coincidence

This year, the 13th day of both February and March will fall on a Friday, creating two Friday the 13ths in a row. Below, we’ll look at our calendar data to find out how unusual that is.

First, though, let’s put our superstitious minds to rest: Based on actual statistics, Friday the 13th is not an unlucky day. Records show no spikes in events such as accidents, hospital visits, or natural disasters.

In that sense, having two Friday the 13ths in a row is, quite literally, a lucky coincidence.

That Special Date

To be clear, February 13 falling on the same day of the week as March 13 is nothing special: It happens in all common years (non-leap years), when February has 28 days. These break down neatly into 4 weeks of 7 days each, so naturally, March begins on the same day of the week as February.

So, in a way, this really shouldn’t make the news—if it wasn’t for the special standing Friday the 13th has in our collective imagination. As a day of unfortunate repute, many of us may think twice about taking risks when it rolls around, as it does, without fail, at least once a year. There’s even an official term for the fear of Friday the 13th: paraskevidekatriaphobia.

Therefore, in our humble opinion, a pair of consecutive Friday the 13ths is a bit special, even if its allure is primarily based on folkloric significance.

New Year’s Thursday and a Short February

So, what are the conditions for this phenomenon to occur?

First of all, it’s worth noting that it can only ever happen in February and March. That is because February is the only month whose length can, in most years, be evenly divided by 7.

But the year itself also has to have certain qualities. It can only happen if:

1. The year starts on a Thursday: February 13 is the 44th day of the year. For it to fall on a Friday, January 1 needs to be a Thursday.
2. It’s a common year (not a leap year): In common years, February has 28 days. This number is evenly divisible by 7, which is the number of days in a week. That means that, in any common year, the 13th of February falls on the same day of the week as the 13th of March. In leap years, February gets an extra day, the 29th of February. 29 is not evenly divisible by 7, so the weekday-date combinations in March don’t match those in February.

Three Times in 28 Years

The last year with a pair of Friday the 13ths was 2015 (11 years ago), and the next will be 2037 (in 11 years). So, at first glance, it may look like this happens every 11 years.

However, looking at the full list of occurrences reveals a more intricate pattern consisting of two gaps of 11 years and one of 6 years: 11, 11, 6, 11, 11, 6, and so on.

This results in an ever-repeating cycle of 28 years (11 + 11 + 6 = 28).

Leap Year Rhythm Determines Cycle Length

So, why does a cycle measure precisely 28 years? Interestingly, this also boils down to 28 being a multiple of 7.

New Year’s Day can fall on 7 possible days of the week, and the repeating pattern must therefore be based on a number evenly divisible by 7. Since the number of days in any year, 365 or 366, is not evenly divisible by 7, the weekday of January 1 changes every year.

Common years have 365 days, which is 52 full weeks, plus 1 day. Without leap years, the days of the week would shift by 1 day each year, so the full cycle would only last 7 years.

However, a leap year adds an extra day to the count, raising the total number to 366 days, or 52 weeks and 2 days . So, every leap year causes the weekday of January 1 of the following year to “jump ahead” by one extra day.

Crucially, a leap year usually happens every 4 years. That is why the cycle spans exactly 28 years (4 x 7 = 28), and not, say, 21 or 35 years.

Leap Year Prevents the Fourth Twin

All this results in the above-mentioned 11-11-6 pattern—but there’s another twist to it: There are actually four years in each 28-year cycle that start on a Thursday. Hence, there are also four Februaries with a Friday the 13th. This happens in an 11-6-5-6 pattern.

However, that extra occurrence, which breaks up the second 11-year span, always falls in a leap year. That means that February has a 29th day, which prevents March 13 from falling on the same day of the week as February 13. It’s only because of that extra February day that we’re spared a fourth pair of consecutive Friday the 13ths.

The next time this happens is 2032.

The Hiccup at Century’s End

In the list of occurrences, eagle-eyed readers may have spotted a break in the pattern toward the end of the 21st century: Interrupting the trusted 11-11-6 rhythm spanning centuries, the years 2099, 2105, and 2111 all have a pair of Friday the 13ths in February and March.

In other words, the 6-year gap—usually a single occurrence sandwiched between two 11-year gaps—suddenly appears 3 times in a row.

This is the consequence of a sub-rule governing leap years in the Gregorian calendar: Leap years occur every 4 years, unless the year is divisible by 100, but not by 400. That means that the year 2100 is not a leap year, breaking the quadrennial leap year pattern and throwing the rhythm of coupled Friday the 13ths into disarray before it resumes its usual cadence for another century.

By the way, the same was not the case in the year 2000, because that number is evenly divisible by both 100 and 400, so it was a leap year, and the pattern continued as though nothing had happened.