Is reciting surah fatiha for deceased sunnah?

Praise be to Allah.

There is no evidence (daleel) for reciting al-Faatihah or any other part of the Qur’aan and giving (the reward for) it to the deceased. We must not do that, because it was not narrated that the Prophet (peace and blessings of Allaah be upon him) or his companions (may Allaah be pleased with them) did any such thing. It is prescribed to make du’aa’ for the dead Muslims and to give charity on their behalf by giving to the poor and needy. In this way a person may draw closer to Allaah and ask Him to give the reward for that to his father, mother or other people, deceased or alive. The Prophet (peace and blessings of Allaah be upon him) said: “When a man dies, all his deeds come to a halt apart from three: ongoing charity (sadaqah jaariyah), beneficial knowledge or a righteous child who will pray for him.”

And it was reported that a man said to the Prophet (peace and blessings of Allaah be upon him): “O Messenger of Allaah, my mother has died and she did not make a will. I think that if she had spoken she would have given in charity. Will she be rewarded if I give in charity on her behalf?” He said, “Yes.” (Saheeh – agreed upon)

Source: islamqa.info

Whenever we are being told "do so and so" without any proof from quran and sunnah. We must ask them to give us proof. The Prophet peace be upon him told us in hadith

Hadith

حَدَّثَنَا يَعْقُوبُ، حَدَّثَنَا إِبْرَاهِيمُ بْنُ سَعْدٍ، عَنْ أَبِيهِ، عَنِ الْقَاسِمِ بْنِ مُحَمَّدٍ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتْ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ مَنْ أَحْدَثَ فِي أَمْرِنَا هَذَا مَا لَيْسَ فِيهِ فَهُوَ رَدٌّ ‏"‏‏.‏ رَوَاهُ عَبْدُ اللَّهِ بْنُ جَعْفَرٍ الْمَخْرَمِيُّ وَعَبْدُ الْوَاحِدِ بْنُ أَبِي عَوْنٍ عَنْ سَعْدِ بْنِ إِبْرَاهِيمَ‏.‏

Narrated Aisha:
Allah's Messenger (ﷺ) said, "If somebody innovates something which is not in harmony with the principles of our religion, that thing is rejected."
Sahih al-Bukhari, 2697
In-Book Reference: Book 53, Hadith 7
USC-MSA web (English) reference: Vol. 3, Book 49, Hadith 861 (deprecated numbering scheme)


It is sufficient to follow what Allah and His Messenger have ordered us.