A: The 4 sacred months are: Rajab, Zul Qa'dah, Zul Hijjah and Muharram.

The Quran says: The number of months in the sight of Allah is twelve (in a year), so ordained by Him the day He created the heavens and the earth; from among them four are sacred. (Surah Taubah)

Hazrat Abu Bakrah (Radiyallahu Anhu) narrates that Rasulullah (ﷺ) said: “…The year consists of twelve months, four of which are sacred. Three from them are consecutive: Zul Qa’dah, Zul Hijjah and Muharram. And (the fourth sacred month) is Rajab…” (Bukhari #4662 and Muslim #1679)

And Allah Knows Best.
Darul Ihsan Fatwa Department