All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger.
We will start our answer with addressing the more important issue, which is the hijaab, and by it, we mean covering the body except for the face and hands. This is the description of the obligatory hijaab according to the consensus of scholars, and it is impermissible to neglect it under any circumstances. There is no specific type of clothing that the Muslim woman is required to wear; however, there are certain conditions that must be fulfilled in her clothes. We have previously highlighted these conditions in fatwas 83033 and 81554. These fatwas also explained the difference of opinion among the scholars regarding the ruling on covering the face. We believe that the preponderant view in this regard is that it is an obligation to cover the face. So, if the woman can adhere to the face cover, then it is safer for her and more likely to keep her distant from the means leading to Fitnah (temptation).
If the woman does not cover her face in principle and only covers it when there is a fear of Fitnah, then that is not wrong. Rather, it is a good thing to do, and this is better than keeping her face uncovered all the time. The majority of the scholars who held that it is recommended to cover the face also held that it is obligatory to cover it when times are corrupt and Fitnah is feared.
On the other hand, the wives of the Prophet, sallallahu ‘alayhi wa sallam, and the female Companions used to uncover their faces while in a state of Ihraam (ritual state assumed for Hajj and ‘Umrah), and they would cover them whenever a non-Mahram man passed by them, because the woman does not cover her face in the state of Ihraam.
Allah knows best.