Charity on behalf of the Deceased
Aishah (radi Allahu anha) reported: A man said to the Prophet (sal Allahu alaihi wa sallam): “My mother has died suddenly. I think that if she were able to talk (alive) she would have given in Sadaqah (charity). So, if I give Sadaqah now on her behalf, will she get the reward?” The Messenger of Allah (sal Allahu alaihi wa sallam) said, “Yes (she will be rewarded for that).”
[Sahih Al-Bukhari and Muslim]
This Hadith plainly tells us that the reward of charity given on behalf of a dead person reaches his or her soul just like the benefit of supplications, if accepted by Allah.
Charity and supplications are two permissible forms of the transmission of blessing (reward) to the dead. However, Qur’an reading meant to transmit reward to a dead man’s soul is not from the Sunnah of the Prophet (sal Allahu alaihi wa sallam). All such observances are of no use to the dead.
Only scriptural (from either the Qur’an or Sunnah) channels can be beneficial to them and they are only two – du’at (supplications) and charity.
And Allah knows best!