Sahih al-Bukhari 4605

Arabic

حَدَّثَنَا سُلَيْمَانُ بْنُ حَرْبٍ، حَدَّثَنَا شُعْبَةُ، عَنْ أَبِي إِسْحَاقَ، سَمِعْتُ الْبَرَاءَ ـ رضى الله عنه ـ قَالَ آخِرُ سُورَةٍ نَزَلَتْ بَرَاءَةَ، وَآخِرُ آيَةٍ نَزَلَتْ ‏{‏يَسْتَفْتُونَكَ ‏}‏

English translation

Narrated Al-Bara:The last Sura that was revealed was Bara'a, and the last Verse that was revealed was: "They ask you for a legal verdict, Say: Allah directs (thus) about those who leave no descendants or ascendants as heirs

Reference: Sahih al-Bukhari 4605, Book of Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh)). English translation by Dr. Muhammad Muhsin Khan.