These Are the Rarest Birthdays in the United States

Updated: May 01, 2024

How popular is your day of birth? Celebrate the rarest birthdays—and the most common!

Happy birthday to you—and you and you! Wait a minute, how many people have the same birthday here? The answer may actually surprise you. According to the “birthday paradox,” in a random group of 23 people, there’s about a 50% chance that at least two people have the same birthday. And that’s the case whether they have one of the rarest birthdays or were born during the most popular birth month. (It’s a math problem with 253 chances for matching birthdays, says the Scientific American.)

So which months have the most birthdays—and better yet, which have the fewest? We’ve got you covered. We have the data on which dates are the most common to celebrate and which are the rarest birthdays, and unlike presents, we’re not afraid to share them. While you may not have the rarest eye color or rarest personality type, having a rare birthday is worth bragging about. So whether you’re a September baby (September babies are more successful, by the way), born during March Madness or anywhere in between, read on to find out where your birthday ranks.

What’s the rarest month to be born in?

According to data collected by the Centers for Disease Control and Prevention (CDC) and the Social Security Administration (SSA), the rarest month to be born in is February, making Aquarius the rarest zodiac sign. This makes logical sense, since February is the shortest month of the year, even with a leap year. Another factor that makes February a rare birth month: Conception would have happened in May, and when the weather is warmer and days are longer, fewer babies tend to be conceived.

What are the rarest birthdays?

February babies are special, but which dates are actually the rarest birthdays? Surprisingly enough, none of the rarest birthdays fall in February. Instead, many of them coincide with major holidays, such as Christmas Day, New Year’s Day and Christmas Eve—how’s that for a birthday meme? This is most likely due to the fact that there are fewer inductions and cesarean sections scheduled during the holidays. These are the rarest birthdays in the U.S. and the average number of births on that day each year.

  • December 25 (6,574 average yearly births)
  • January 1 (7,792 average yearly births)
  • December 24 (8,069 average daily births)
  • July 4 (8,796 average yearly births)
  • January 2 (9,307 average yearly births)
  • December 26 (9,543 average yearly births)
  • November 27 (9,718 average yearly births)
  • November 23 (9,883 average yearly births)
  • November 25 (9,954 average yearly births)
  • October 31 (9,978 average yearly births)

What’s the most common birth month?

August is not only the month of long sunny days and back-to-school bonanzas, it’s also the most common birth month. The CDC data shows that July, August, September and October tend to be the most popular birth months in the U.S., making the colder, cozier winter months the most popular time to conceive.

What are the most common birthdays?

While having one of the rarest birthdays can be pretty cool, having one of the most common birthdays is also a win—just think of all the people across the country celebrating alongside you. And while August may be the most common birth month (and October babies tend to live longest), almost all the most common birthdays happen to be in September. Virgos, get the birthday quotes ready, this one is for you.

  • September 9 (12,301 average yearly births)
  • September 19 (12,229 average yearly births)
  • September 12 (12,224 average yearly births)
  • September 17 (12,148 average yearly births)
  • September 10 (12,144 average yearly births)
  • July 7 (12,108 average yearly births)
  • September 20 (12,107 average yearly births)
  • September 15 (12,087 average yearly births)
  • September 16 (12,072 average yearly births)
  • September 18 (12,055 average yearly births)


Birthday cake with colorful candlesWestend61/Getty Images

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