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 is His slave and Messenger.
Having a non-Muslim maid in a Muslim's house is permissible, provided the conditions and precautions concerning a non-Mahram woman be taken into consideration.
As a fact, only few people are aware of the following conditions:
It is not permissible for any male member of the family to remain alone with the woman servant. It is apparent to everyone that implementing this rule is almost impossible. The situation becomes worse if a maid is non-Muslim since she will badly affect the family members through her un-Islamic character and beliefs.
Moreover, the whole body of a Muslim woman except her face and hands is considered ‘Awrah in front of a non-Muslim woman according to the view of the majority of the Muslim scholars. Thus, she (maid) is not supposed to see except the faces and hands of the Muslim women in the house.
Therefore, we advise every Muslim to be conscious as far as his religion is concerned.
No doubt, having a Muslim maid is better than having a non-Muslim one. One should also search for a pious Muslim servant not just any Muslim, as a dissolute Muslim also sometimes causes much harm to the family members.
For more benefit on the rules of having a maid in one's house, please refer to Fataawa 92230, 91455 and 129682.
Allah knows best.