Is tonight (Thursday- erev Shabbos/Rosh Chodesh) considered Rosh Chodesh Re: Taking haircuts?
For those who are careful concerning the instructions of R’ Yehuda Ha-Chassid, and therefore refrain from taking haircuts on Rosh Chodesh, some write that they should do so even on Rosh Chodesh that falls on Friday. However, others are lenient concerning this, and one can be lenient if a haircut is in order.
The Mishnah Berurah (260:7) writes that some are careful for the instructions of R’ Yehuda Ha-Chassid and therefore don’t take a haircut on Rosh Chodesh, even on Erev Shabbos.
However, in Siman 493 (5) he writes that where Rosh Chodesh Iyar falls on Shabbos it is permitted to take a haircut on Friday, even though Friday is invariable also Rosh Chodesh, indicating that it is permitted to do so on Erev Shabbos. This can be understood to indicate that even those careful for R’ Yehuda Ha-Chassid need not be concerning on Erev Shabbos – a ruling issued by Rav Moshe Feinstein (Le-Torah Ve-Horaah II, Year 5733).
However, it is possible that the Mishnah Berurah simply didn’t mention the matter of R’ Yehuda Ha-Chassid, and we find in the Chasam Sofer (Orach Chaim 158) that haircuts are not taken on Rosh Chodesh even on Erev Shabbos.
Yet, for Iyar we find lenient rulings in Shut R’ Taaya Weil (no. 40) and in the Peri Megadim (493, Eshel Avraham 5), and there is therefore room for leniency where a haircut is in order.