Forwarding Reward of Good Acts to Deceased:
Hakim al-Umma Mawlana Shah Asharaf Ali Thanawi ra said;
“Making isla-e-sawab (forwarding the reward of good deeds to the deceased) according to the preferential (mustahib) method is a later thing.
The first and most important thing to do is to find out if the deceased had any outstanding debts/loans. If there are any loan/debts pending, it is obligatory (fardh) to settle them foremost.
If there are no loans/debts or after paying them some things remain of the heritage, find out if the deceased made some will (waseyat).
After settling all this, when the (remaining) heritage becomes the legal property of inheritors then instead of the ceremonial and prevalent modes of good acts and customs it is most beneficial to find out if the deceased had any outstanding (qadha) prayers (salah), fasts (seyam), zakah, etc. If there are any of these outstanding, then pay compensation (fidya) for them. This amount should be distributed amongst the needy poor, orphans and widows in the local neighborhood.
This from of isal-e-sawab is superior to other (nafil) modes.”
(Al-Ifadhatul-yomia Volume 7 pg 40)