A small detail on the birth record can move the whole Bar Mitzvah date. Was he born before or after nightfall? Was it in Adar? Was it a leap year? Settle those questions before you book anything.
Born after dark
The Hebrew day begins at nightfall, not at midnight. A boy born after nightfall has the next Hebrew date. For example, a boy born on Thursday 16 January 2014 before nightfall was born on 15 Shevat 5774. His Hebrew birthday is Saturday 23 January 2027, and he reads Beshalach. If he was born after nightfall, he was born on 16 Shevat, his birthday is Sunday 24 January 2027, and he reads Yisro on 30 January. One hour on the birth record moved him a whole portion.
Born in Adar
In a leap year the Hebrew calendar has two months of Adar, Adar I and Adar II. That makes the Adar birthdays a special case. The usual Ashkenazi and Chabad practice is this:
Born in Adar in a regular year, and his 13th year is a leap year: he becomes Bar Mitzvah in Adar II.
Born in Adar I or Adar II in a leap year: he keeps that month in a leap year, and plain Adar in a regular year.
For example, a boy born on Monday 13 March 2017 was born on 15 Adar 5777. His 13th year, 5790, is a leap year. The usual practice gives him 15 Adar II 5790, which is Wednesday 20 March 2030, and he reads on Shabbat 23 March. If you counted Adar I, you would get 18 February 2030, a month earlier. Sephardi custom can differ, so ask your own Rabbi.
Born on 30 Cheshvan or 30 Kislev
In some years these months have only 29 days. A boy born on the 30th of one of them needs a Rabbi to name his date.
What if he was born in the twilight, between sunset and nightfall? That is a genuine doubt, and the answer is for a Rabbi. Ask your own Rabbi before you fix the date.
Does a leap year change the date? It can. The extra month is Adar I, and the usual Adar becomes Adar II. A boy born in Adar, or whose 13th year is a leap year, needs the care described above.
Who decides the date for our family? Your own Rabbi. Communities differ on the Adar cases, so a calculator gives you the starting point, not the ruling.
If the date is uncertain, bring it to the assessment
In a 30-minute Zoom assessment, Rabbi M. Sabbah hears your son read and tells you how many months he needs. Once your Rabbi has settled the date, you will know exactly how long he has. If you continue, the assessment is credited in full toward the first month.
