Praise be to Allah.
The scholars differed concerning the ruling on whether Muslim women can take off their hijaab in front of non-Muslim women, because they differed in their interpretation of the aayah in Soorat al-Noor (interpretation of the meaning):
“… and not to reveal their adornment except to their husbands… or their women…” [al-Noor 24:31].
There are three views concerning the Tafseer of this phrase:
That it means Muslim women;
That it means all women, Muslim and non-Muslim;
That it means Muslim women preferably but this is not binding.
The more correct view – and Allaah knows best – is that it is permissible for a Muslim woman to appear (without hijaab) in front of a kaafir woman, unless she fears that the woman may describe her to her husband or to any other stranger (non-mahram man). In that case she has to keep her hijaab on in front of that woman. There is no difference between a kaafir woman and a corrupt Muslim woman in this case.
Among the evidence (daleel) that it is permissible to take off hijaab in front of a kaafir woman is the hadeeth of ‘Aa’ishah (may Allaah be pleased with her) in which she mentions that a Jewish woman came in to see her and said, “May Allaah protect you from the torment of the grave…” (Narrated by al-Bukhaari, 1007; Muslim, 584).
Shaykh ‘Abd al-‘Azeez ibn Baaz (may Allaah have mercy on him) said:
“It is not obligatory to wear hijaab in front of them – non-Muslim women – because they are like all other women according to the more correct of the two scholarly views.”
(Fataawaa al-Mar’ah al-Muslimah, 2/582).
What the Muslim woman can uncover in front of a kaafir woman is the same as what she can uncover in front of her mahrams, i.e., the places of adornment or the places of wudoo’.
Shaykh Muhammad Saalih ibn ‘Uthaymeen said: “In front of her mahrams she can uncover her face, head, neck, hands, forearms, feet and calves, and she should cover everything else.”
(Fataawaa al-Mar’ah al-Muslimah, 1/417).
And Allaah knows best.