Essale Sawaab

Esaale Sawaab (to perform a virtuous act and grant the reward to any person, alive or deceased) is permissible and in fact praiseworthy (Mustahab).

There are 2 types of Esaale Sawaab:

• The conveying of the reward of charitable deeds.
• The conveying of the reward of physical deeds that do not require wealth, e.g. Salat, Fasting, Zikr, Recitation of the Holy Quran, Tawaaf of the Kaabah, etc.

The first form is unanimously acceptable by the Ahle Sunnah Wal Jamat.

The second form is correct according to the Hanafi and Hanbali Madhab and several Shafi and Maliki scholars as well.
 
In Holy Quran it says:

"And lower your wing humbly for them, with mercy, and pray, "My Lord! Have mercy on them both, the way they brought me up in my chilhood." (Bani Israel 17:24)

In this verse Allah commands all believers to seek mercy for their parents. So what is your opinion, Will the command of Allah not the hold any benefit for the deceased.

Hazrat Anas (R.A) asked the Holy Prophet (S.A.W):

“If we send Sawaab to the deceased, give Sadaqa and Khayraat and ask Dua for them, does this reach  them?”.

The Prophet (S.A.W) said: “Verily it reaches them. Read Salaah for them as you read for yourself and fast for them as you fast for yourself”.

Hazrat Abu Huraira (R.A) reported that Prophet (S.A.W) has said:

“When a man dies, his acts come to an end, except for three. These being, (1) Recurring charity, (2) Knowledge (by which people benefit), and a (3)Pious son, who prays for him (for the deceased)”. (Muslim Shareef)