# Global and regional birthday frequency trends

> Live situation record from CLSTR: https://clstr.news/situations/global-and-regional-birthday-frequency-trends
> Updated: 2026-09-30T06:19:15.000Z. Sources: 7. Developments: 2.

Global statistics indicate that September is the most frequent month for birthdays, with September 16 identified as the most common specific date. Some theories suggest this peak may be linked to conception rates during the December holiday season, while the rarest birthdays, such as January 1 and December 25, are attributed to lower hospital delivery rates during holidays.

In the Netherlands, data from Statistics Netherlands (CBS) confirms September as the peak birthday month, noting that September 30 is the busiest day with approximately 44,000 birthdays. Dutch demographic trends show a generational shift where individuals born after 1980 are more frequently born in late summer and early autumn, whereas those born between 1940 and 1980 tended to have spring birthdays. Experts suggest the introduction of the contraceptive pill in the 1960s may have facilitated these shifts by allowing for more pregnancy planning.

## Timeline

### 2026-09-30: September identified as peak birthday month in the Netherlands

Statistics Netherlands reports that September is the peak month for birthdays, with September 30 being the most common date, while January 1 sees the fewest.

5 sources. https://clstr.news/cluster/september-identified-as-peak-birthday-month-in-the-netherlands

### 2026-09-05: September identified as month with most frequent birthdays

Statistical data shows September is the most common month for birthdays, with September 16 being the most frequent date. February 29 remains the rarest due to leap year occurrences.

2 sources. https://clstr.news/cluster/september-identified-as-month-with-most-frequent-birthdays

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Cite as: Global and regional birthday frequency trends. CLSTR, https://clstr.news/situations/global-and-regional-birthday-frequency-trends