In what month is the last verse of the Quran revealed?
“…This day have I perfected your religion for you and completed MY favor upon you and have chosen for you Islam as religion…” (Al Quran # 5:3)
Arguably, it is understood by the scholars that the above-mentioned narrative which is the part of Verse 5:3, revealed during the time of Prophet’s (pbuh) Last Sermon at the time of Hajj, would be the last Verse to reveal. Because once it is declared that the religion is complete/perfected no further revelation is required.
Hence, the answer to the question is, Verse 5:3 is the last Verse and was revealed during the time of Hajj.
Caliph Omar has said:
“I know definitely on what day this Verse was revealed; it was revealed on the day of ‘Arafat, on a Friday.”
It was 9th of Dhu Al-Hijja, 10 th Hijri; Friday, 6th of March, year 632.Source