7,552 residents of Slovenia do not celebrate 1 January only as the start of the New Year but this date is written as birthday in their official documents. Since in the past many parents of children born on the last day (or days) of the year did not follow the rules and reported birth as of 1 January, the fewest residents of Slovenia have their birthdays on 31 December (4,731). Such reporting of birth was possible as long as most of the children were not born in maternity hospitals or other health institutions that report childbirth. The ratio of residents born on 1 January and 31 December is 1.6 vs 1. No two days of the year have such a large ratio.

After 1970, when the share of children born in a maternity hospital grew to 96% and the possibility of misreporting the birthday was diminished, the number of residents born on 1 January and 31 December became almost the same. With incorrect registration of birth parents could keep their children at home longer and enrol them in school a year later. This was particularly important for boys as they could go serve in the military a year later. This artificial postponement of births changed the gender ratio. Biologically always more boys than girls as born, while in December of some years according to official data more girls than boys were born.

In the past ten years the number of children born on 1 January declined by 250 and the number of children born on 31 December by 100.

The second highest number of births on 1 October: 6,375
On 1 October the second highest number of children is born. 6,375 residents of Slovenia celebrate their birthday on that day. The number of birthdays is significantly high also in the last third of September, about nine months after the Christmas / New Year holidays. In that period about 6,100 to 6,200 residents celebrate their birthdays each day.

If you would like to know how many residents of Slovenia have their birthdays on the same day as you, you can find the data in the interactive search engine Names and Birthdays.