Tanit Bechorot

Source: Halachipedia: Tanit Bechorot

Link: https://halachipedia.com/index.php?title=Tanit_Bechorot

Categories: Fasting, Holidays, Pesach

Exported: 2025-12-30

The reason for the fast

In commemoration of the miracle that Hashem saved the firstborn Jews from the plague of the firstborn, the firstborns fast on Tanit Bechorot, which is on Erev Pesach.¹

Which firstborns are obligated to fast?

A firstborn of one’s mother or the firstborn of one’s father (or both) should fast on Erev Pesach.² The reason is that Hashem killed both the firstborns of the father and of the mother in Egypt.³
Even a Levi or Cohen should fast.⁴
A groom within 7 days of the wedding doesn’t have to fast on Tanit Bechorot.⁵
A firstborn born through a caesarian section or firstborn after a miscarriage should also fast.⁶

Women

The Ashkenazic minhag is that women don’t fast.⁷ This is also the Sephardic minhag.⁸ Even for those who the custom is for women to fast, if the woman is pregnant or nursing she shouldn't fast.⁹

Children

A father should fast in place of his son who is a firstborn but is under Bar Mitzvah. According to the minhag to listen to a Siyum, the father should go to the Siyum in place of his son.¹⁰
If the firstborn child isn't yet 30 days old the father doesn't have to fast or listen to a siyum but if it is possible to do so he should.¹¹
The Rama writes that if the father is a firstborn, the mother should fast for her firstborn son who is under Bar Mitzvah.¹² However, the Mishna Brurah quotes some poskim who say that the father's fast counts for the son as well. Therefore, the Mishna Brurah allows a mother to be lenient if she is in pain.¹³
The Aruch HaShulchan writes that we no longer have the minhag that a parent should fast for a firstborn son who is under Bar Mitzvah.¹⁴
If the father is a firstborn and also has a young son who is a firstborn, it is sufficient for the father to hear a siyum for both of them.¹⁵

Those who are unable to fast

One who has an ache in his eyes or head is not required to fast.¹⁶
If someone will only be able to eat a very small amount because of the fast and won’t be able to fulfill the mitzvot of Matzah and 4 cups of wine, one shouldn’t fast. Nevertheless, it is preferable that he just have snacks and not a meal.¹⁷

Tanit Bechorim on Friday and Shabbat

If Erev Pesach falls out on Friday, the fast should take place on that day.¹⁸

Minhag to join a Siyum

See the Siyum Masechet page for more details

References

¹: Mishna Brurah 470:1, Kaf HaChaim 470:1, Tur 470:1. The original source for this fast is Masechet Sofrim 21:3. Kaf Hachayim 470:30 explains that even though the miracle happened on the fifteen we fast on the fourteenth because we don't fat on yom tov.

²: Shulchan Aruch O.C. 470:1

³: Mishna Brurah 470:2, Kaf Hachayim 470:2.

⁴: Mishna Brurah 470:2

⁵: Kovetz MeBet Levi (Nissan 5761 pg 86). Rav Ovadia Yosef in Yabia Omer 1:25 says he should try to participate in a seudat mitzva.

⁶: Guide to Practical Halacha (v. 5 p. 142 n. 4-5) quoting the Debrecener

⁷: Rama 470:1, Mishna Brurah 470:4

⁸: Although Shulchan Aruch O.C. 470:1 holds that women firstborns should fast Tanit Bechorot and Rav Ovadia Yosef in Sh”t Yechave Daat 3:25 and Sh”t Yabia Omer 4:42 upheld that minhag, nonetheless, in Chazon Ovadia Pesach p. 207-8 he concluded that it wasn't the minhag today. Rav Shlomo Amar in Haggadah Myamim Yamim agrees. Kaf HaChaim 470:17 quotes the Chida (Machazik Beracha 470:2) and Ben Ish Chai (Parashat Tzav) that the Sephardic minhag is to follow the Rama that women do not fast Tanit Bechorot.

⁹: Mishna Brurah 470:9, Kaf Hachayim 470:15 and 21.

¹⁰: Rama 470:2, Piskei Teshuvot 470:6, Yalkut Yosef 470:19, Yosef Daat (Dinei Chinuch 16:3)

¹¹: Yalkut Yosef 470:19

¹²: Rama 470:2

¹³: Mishna Brurah 470:9

¹⁴: Aruch HaShulchan 470:4

¹⁵: Rav Hershel Schachter (YIW Packet) held that it is sufficient for the father to hear the siyum for himself since it is a stringency anyway for the son to have to hear the siyum. He said that is the minhag unlike the Nitai Gavriel 2:42:5 quoting the Beer Moshe who held that it is necessary for the father to listen to a siyum for himself and the mother to hear a siyum for herself.

¹⁶: Mishna Brurah 470:2

¹⁷: Mishna Brurah 470:2

¹⁸: Mishna Brurah 470:5, Chazon Ovadyah Pesach pg 101 (5763 edition, pg 117)