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.
The ruling of the Sharee’ah concerning inheritance establishes that people of different religions do not inherit from one another although there are some details concerning this matter.
So, the Muslim does not inherit from the non-Muslim and vice-versa. The evidence is the Hadeeth reported from the Prophet that he said: “The believer does not inherit from the disbeliever neither does the disbeliever inherit from the believer.” [Al-Bukhari]
Ibn Qudaamah relates in his book “Al-Mughni” that there is a consensus among Muslim scholars that the Muslim does not inherit from the non-Muslim and the above Hadeeth is enough evidence for this. Now, if the person is in a Muslim country, he can leave the issue to the Muslim authorities that deal in such matters. If the Muslim lives in a non-Muslim country, then he should emigrate to a Muslim country. The Prophet said “I am exempt of any Muslim who lives among non-Muslims.” [Abu Daawood]
However, if the person is compelled for some reasons to live in a non-Muslim country, and if he fears that his belongings will not be given out after his death – as stipulated in the Sharee’ah, then, it is permissible to make a will for his poor relatives even if they are Christians. His will should be carried out in the third portion of his belongings. The rest of his money should be spent for the general benefit of Muslims.
So, if you can guarantee that Muslims get their rights from your inheritance, that is what should be done; otherwise, know that Allah does not place a burden on anyone that he cannot bear.
For more benefit that a Non-Muslim does not inherit a Muslim and vice-versa, please refer to Fataawa 358765, 238165, 96163, 189195, 137484 and 95466.
Allah knows best.