Hadith Evidence
Narration from Sahih Muslim:"In the last two Rak‘ahs, he (ﷺ) would recite only Surah Al-Fatihah."
[Sahih Muslim: 451]
Key Rulings & Benefits
In the last two Rak‘ahs of a four-Rak‘ah Salah (Dhuhr, Asr, Isha), only Surah Al-Fatihah should be recited.Similarly, in the third Rak‘ah of Maghrib, only Surah Al-Fatihah is recited.
If someone recites an additional Surah in these Rak‘ahs, there is no sin, but it is against the Sunnah practice.
This ruling is derived from the book "Diya al-Islam fi Sharh al-Ilmam bi-Ahadith al-Ahkam" by Shaykh Taqi al-Din Abi al-Fath, translated by Maulana Mahmood Ahmad Ghaznfar.Conclusion
The Sunnah practice is to recite only Surah Al-Fatihah in the last two Rak‘ahs of four-Rak‘ah Salah and the third Rak‘ah of Maghrib.Adding another Surah is not sinful but is not the preferred Sunnah.
