Sunan an-Nasa'i, Volume 3, Book 23, Hadith 2480 (DarusSalam) ⓘ

It was narrated that 'Ali, may Allah be pleased with him, said: "The Messenger of Allah said: 'I have exempted you from (having to pay Zakah on) houses and slaves, and there is no Zakah on less than two hundred (Dirhams)."

أَخْبَرَنَا حُسَيْنُ بْنُ مَنْصُورٍ، قَالَ حَدَّثَنَا ابْنُ نُمَيْرٍ، قَالَ حَدَّثَنَا الأَعْمَشُ، عَنْ أَبِي إِسْحَاقَ، عَنْ عَاصِمِ بْنِ ضَمْرَةَ، عَنْ عَلِيٍّ، رضى الله عنه قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ قَدْ عَفَوْتُ عَنِ الْخَيْلِ وَالرَّقِيقِ وَلَيْسَ فِيمَا دُونَ مِائَتَيْنِ زَكَاةٌ ‏" ‏ ‏.‏