The Customary Prohibition of Haircuts
As a result of the mourning observed during the “Three Weeks,” the Ashkenazi custom is to abstain from shaving and taking haircuts beginning from the Seventeenth of Tammuz until the Tenth of Av.
Nevertheless, the Sephardic custom is not as stringent and follows the letter of the law established by a Tannaic enactment (following the destruction of the Bet Hamikdash) which is to prohibit taking haircuts and laundering clothing during the week during which Tisha Be’av falls out. The Rambam and Maran Ha’Shulchan Aruch rule likewise. Those Sephardic Jews who study with or live in close proximity to Ashkenazim may act stringently and abstain from shaving and taking haircuts from the Seventeenth of Tammuz.
The week during which Tisha Be’av falls out refers to the very week the fast of Tisha Be’av is observed, beginning from Sunday of that week. For instance, if Tisha Be’av occurs on Tuesday, as it does this year, all of the mourning customs associated with the week during which Tisha Be’av falls out begin from the previous Sunday.
Haircuts for Women
Regarding a woman taking a haircut during the week during which Tisha Be’av falls out or during the “Three Weeks” according to the Ashkenazi custom, this depends on a related disagreement among the Poskim, as follows:
The Poskim disagree regarding whether a woman who is in mourning for one of seven relatives (father, mother, brother, sister, son, daughter, or husband) is forbidden to take a haircut just as it is forbidden for a male mourner or perhaps, this prohibition does not apply to women.
Halachically speaking, Maran Ha’Shulchan Aruch, whose rulings are followed by Sephardic and Middle Eastern Jews, writes that the prohibition to take a haircut does not apply to women. Thus, immediately following the initial seven days of mourning (Shiva), a woman may take a haircut. Nevertheless, the Rama, whose rulings are followed by Ashkenazi Jews, writes that the prohibition to take a haircut applies to women as well.
It therefore seems that according to Maran Ha’Shulchan Aruch and the Sephardic custom, the prohibition to take haircuts observed in mourning the destruction of the Bet Hamikdash does not apply to women either. However, according to the Rama and the Ashkenazi custom, women are also included in this prohibition. Hagaon Harav Moshe Feinstein zt”l and other great Poskim rule likewise.
On the other hand, there are Ashkenazi Poskim who write that although women are prohibited to take haircuts while in actual mourning for a relative, nevertheless, woman may, in fact, act leniently and take haircuts during the “Three Weeks,” for this (not taking haircuts throughout the entire “Three Weeks”) is not as much a halachic prohibition according to the letter of the law as it is a custom which has been accepted. However, during the week during which Tisha Be’av falls out, when it is an actual prohibition to take a haircut based on the edict of the Sages of the Mishnah and not merely customary, there is no distinction between men and women.
Halachically speaking, according to the Ashkenazi custom, men abstain from taking haircuts from the Seventeenth of Tammuz while the Sephardic custom is to permit this until the week during which Tisha Be’av falls out. Regarding women, those who wish to act leniently, even among Ashkenazi women, have on whom to rely.