Can Missed Prayers of a Deceased Person Be Performed by Others?
Source: Aḥkām wa Masā’il – Discussion on Ṣalāh, Volume 1, Page 126
❖ Question
Can someone perform the missed prayers of a deceased person on his behalf?
❖ Answer
Al-ḥamdu lillāh, waṣ-ṣalātu wa-s-salāmu ʿalā Rasūlillāh, Ammā Baʿd!
There is no mention in Qur’ān or Sunnah that the prayers missed by a deceased person during his life can be performed on his behalf.
Thus, if someone did not perform his obligatory prayers during life and passed away, his heirs or relatives cannot perform those prayers for him.
◈ Acts of Worship That Can Be Performed on Behalf of the Deceased
✔ Fasting (Ṣawm):
The Messenger of Allah ﷺ said:
«مَنْ مَاتَ وَعَلَيْهِ صِيَامٌ صَامَ عَنْهُ وَلِيُّهُ»
(Muttafaqun ʿalayh)
"Whoever dies while obligated to fast, his guardian should fast on his behalf."
(Ṣaḥīḥ al-Bukhārī, Kitāb al-Ṣawm, Bāb Man Māta Wa ʿAlayhi Ṣawm)
✔ Ḥajj:
Ṣaḥīḥ Muslim records that if Ḥajj was obligatory on a person but he died without performing it, then a close relative may perform Ḥajj on his behalf.
✔ Debt and Zakāh:
If the deceased had unpaid debts or unfulfilled zakāh obligations, his heirs or others may discharge them on his behalf. This is also established from Qur’ān and Sunnah.

Missed prayers cannot be performed on behalf of the deceased. However, fasting, Ḥajj, debt repayment, and zakāh obligations can be fulfilled on his behalf, provided they were due during his lifetime.
"ھذا ما عندي والله أعلم بالصواب"