The Sunna has many traditions about wills. The collections of Hadith, including Ṣaḥīḥ Muslim and Ṣaḥīḥ al-Bukhāri, report that the Prophet Muhammed (PBUH) said:
“It is not permissible for any Muslim who has something to will to stay for two nights without having his Last Will and Testament written and kept ready with him.”
In the Qur’an, Allah directed Muslims to make a will
“It has been ordained upon you, when death is near one of you, leaving wealth behind, to make a will in favor of parents and close relatives, impartially. This is incumbent upon the pious” (2:180).
God also explained that you must deduct any bequests and debts from your gross estate before distribution to Islamic heirs (Qur’an 4:11). Allah also says:
“When death draws near one of you… it is time to make a bequest” (5:106).