When do I celebrate my birthday in a leap year?

Question:

I was born in the month of Adar during a non-leap year. This year, a leap year, there are two Adars, so when do I celebrate my birthday?

Answer:

You are lucky—you get to celebrate your birthday twice this year! You celebrate your birthday both on Adar I, and then once again one month later during Adar II. (Give your family advance notice that you expect double the gifts and two cakes too...)

(For more information about leap years, see Years. To find out how to Jewishly celebrate your birthday, see How Do Jews Celebrate Birthdays?)

With regards to a Bar Mitzvah, the issue is a bit more complex. While both Adar birthdays are special and should be celebrated, there is question which one is the primary birthday and which one is the secondary one. A Bar Mitzvah marks a boy's entry into adulthood—and this would only occur on the primary birthday.

Since the matter is unresolved, we do not count a Bar Mitzvah boy as part of a minyan or call him up for an aliyah to the Torah until after his Adar II birthday. However, because of the possibility that the boy reached adulthood in Adar I, he should begin laying tefillin in Adar I.1

The above only applies to one who was born in a non-leap year. One who was born during a leap year celebrates his birthday (and Bar Mitzvah) only during the month when he was born.

(See also In a leap year, in which Adar do I observe Yahrtzeit?)

Rabbi Eliezer Posner