Studies Reveal Most Common Birthdays: Is Yours One of Them?

Every year, millions of babies enter the world.

But have you noticed how some birthdays seem to pop up more often in your social circle?

It’s not just chance – certain dates show up much more frequently on birthday calendars across the United States.

Some days bring 12,000+ new babies, while others see fewer than 6,000 births.

What makes some dates so popular for births? The timing of holidays, seasons, and even the weather can influence when babies are born.

Let’s look at the most common birthdays in America and understand the patterns behind these special dates.

This blog sheds light on what makes certain days bring more birthday celebrations than others.

Top Most Common Birthdays

1. September 9 – The Most Common Birthday

September 9 holds the top spot for births in the United States, with an average of 12,301 babiesborn on this date.

This day has produced notable personalities like Adam Sandler, Hugh Grant, and Michelle Williams.

The data collected over 20 years (1994-2014) by the National Center for Health Statistics shows this date consistently ranks highest for births nationwide.

2. Other Popular Birthdays Between September 9-20

The middle of September brings a significant spike in births.

September 19 sees 12,229 babies arrive, while September 12 welcomes 12,224 new births.

This pattern isn’t random – it points to conception timing around the winter holidays.

Many parents-to-be spend more time together during December festivities, leading to more September births.

3. The Impact of Summer Birthdays

While September dominates the birth calendar, July 7 stands out with 12,108 births.

This summer date’s popularity shows interesting patterns around the July 4th holiday.

Many families plan their medical visits around holiday schedules, and hospitals see different staffing patterns during these times.

The warm weather also affects birth timing – research shows slight increases in spontaneous labor during temperature changes.

This makes summer a busy time for birth centers and hospitals.

Least Common Birthdays and Why they are Rare

1. The Impact of Major Holidays

Major holidays show notably lower birth rates, with Christmas Day (December 25th) recording the fewest births in the U.S.

The numbers drop significantly on this day, followed by New Year’s Day (January 1st), Christmas Eve (December 24th), and Independence Day (July 4th).

This pattern links directly to hospital scheduling – medical teams plan fewer optional procedures like C-sections and induced labor during these dates.

Most families and medical staff prefer to schedule births on non-holiday dates, allowing everyone to spend these special days with their loved ones.

2. Leap Day Babies

February 29th stands alone as a truly rare birthday, showing up just once every four years.

These special birthday folks, often called “Leaplings,” make up a small group – only about 5 million people worldwide.

Most Leaplings mark their birthdays on February 28th or March 1st in non-leap years, but they get to enjoy an extra-special celebration during leap years.

Some even say they’re only a quarter of their actual age, bringing fun and humor to their unique birth date.

Why Do Certain Birthdays See More Births?

1. Seasonal Trends

The data shows clear patterns between weather and birth rates.

During cold months, people spend more time inside their homes, leading to higher conception rates.

Shorter daylight hours and dropping temperatures in winter months line up with increased pregnancy rates.

This natural pattern helps explain why we see more babies born in late summer and early fall.

The body’s response to seasonal changes, including shifts in sleep patterns and time spent indoors, plays a role in these trends.

2. Cultural and Societal Factors

Many parents think carefully about birth timing, often considering school calendars.

Children born in September start school as the oldest in their class, which some parents see as helpful for their child’s growth and learning.

This thinking leads some families to plan winter conceptions.

Research shows that families often consider practical factors too – like having a newborn during mild weather months or timing parental leave with slower work periods.

These choices, combined with natural seasonal patterns, create clear peaks in birth dates throughout the year.

Where Does Your Birthday Rank?

Wondering how common your birthday is? In this section, we’ve listed all 366 birthdays (yes, even February 29) as most or least common.

September 9
September 19
September 12
September 17
September 10
July 7
September 20
September 15
September 16
September 18
December 20
September 26
September 8
September 23
December 29
August 8
September 24
July 8
December 19
August 29
August 15
September 22
December 30
September 14
September 25
September 27
July 1
December 28
August 28
July 2
August 22
September 21
September 13
August 30
July 11
August 16
August 1
July 18
August 20
July 9
July 16
July 25
July 15
August 12
July 10
August 27
August 9
October 1
July 17
July 23
August 14
July 22
August 18
July 14
December 21
December 18
October 3
December 27
July 21
August 23
August 21
August 19
February 14
August 26
July 28
August 5
August 11
July 24
July 30
July 29
June 27
August 7
August 6
July 26
August 2
August 25
October 2
September 29
August 4
November 21
July 12
June 28
October 10
August 31
September 28
August 17
June 30
July 19
May 23
July 31
September 11
June 20
August 10
October 4
September 30
July 6
December 17
August 13
August 24
November 20
December 12
September 5
July 20
July 27
June 25
September 7
December 22
June 26
May 24
December 16
June 29
November 1
June 2
June 18
October 6
August 3
June 24
October 7
October 8
November 7
July 3
June 21
October 17
September 6
June 14
May 22
May 16
October 24
October 5
October 11
June 16
October 15
June 3
November 19
May 21
June 17
December 1
June 23
June 6
November 14
November 15
June 10
June 4
April 4
September 4
June 12
May 20
November 5
December 15
February 15
October 25
December 2
March 21
July 13
November 8
June 19
November 18
June 5
June 1
June 7
June 11
May 15
October 22
October 18
October 14
February 7
December 3
November 11
March 17
October 9
December 5
November 3
June 22
March 1
November 4
November 17
May 17
September 3
March 14
October 16
May 2
February 22
October 28
March 7
June 9
November 6
November 2
June 15
November 12
March 3
May 5
May 10
May 14
October 20
February 8
April 11
October 21
February 28
January 24
October 23
March 28
June 13
May 9
November 10
October 27
June 8
January 10
November 16
January 4
May 12
February 10
February 11
October 12
October 29
March 15
February 21
April 2
April 18
March 12
March 20
May 1
September 2
May 19
April 25
March 4
December 4
March 5
March 8
January 14
January 11
March 25
February 25
March 22
December 6
May 8
March 18
January 5
April 12
December 14
December 10
January 25
May 6
February 2
February 16
May 7
February 18
March 10
January 12
March 11
September 1
February 1
October 26
February 23
November 9
January 7
March 24
March 6
March 19
January 6
April 16
February 4
February 24
May 3
January 17
May 30
April 5
May 18
April 3
February 12
April 17
March 27
February 9
December 8
April 19
April 8
March 26
February 20
January 18
January 31
December 11
April 15
April 26
April 22
March 29
January 23
April 23
April 7
February 27
November 30
December 13
February 17
October 19
December 9
April 24
January 26
February 3
January 28
April 9
May 25
April 10
January 20
January 21
January 27
April 21
October 30
January 3
April 14
April 28
March 2
May 28
February 6
May 29
March 31
March 16
October 13
March 9
November 29
January 30
May 11
November 13
December 7
March 23
April 29
April 30
February 26
May 31
May 4
April 20
March 30
May 13
May 27
January 19
February 5
January 22
February 19
April 27
November 22
March 13
April 6
January 9
January16
January 13
January 8
February 13
January 29
January 15
July 5
May 26
December 31
April 13
December 23
April 1
November 28
November 26
November 24
October 31
November 25
November 23
November 27
December 26
January 2
July 4
December 24
January 1
December 25
February 29

Conclusion

Birth patterns tell us much more than just numbers – they show how our lives flow with the seasons and society’s rhythms.

September 9th’s spot as the most common birthday, with 12,301 births, reflects how many families welcome their little ones as summer turns to fall.

On some dates, like December 25th and February 29th, there are fewer births, and each birthday holds its own special story.

These patterns help hospitals staff their teams better, and schools plan their classes.

But in the end, what matters most isn’t if you share your birthday with many others or just a few – it’s the joy each birth brings to families and the unique life that follows.

Studies Reveal Most Common Birthdays: Is Yours One of Them?

Top Most Common Birthdays

1. September 9 – The Most Common Birthday

Most Popular Birth Months

1. September Leads the Pack

2. Other High Birth Months