وَعَنْ سَهْلِ بْنِ أَبِي حَثْمَةَ رَضِيَ اَللَّهُ عَنْهُمَا
قَالَ: أَمَرَنَا رَسُولُ اَللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ -«إِذَا خَرَصْتُمْ، فَخُذُوا، وَدَعُوا اَلثُّلُثَ، فَإِنْ لَمْ تَدَعُوا اَلثُّلُثَ، فَدَعُوا اَلرُّبُعَ»
“We were commanded by the Messenger of Allah (sallallahu alayhi wa sallam), ‘Whenever you assess the amount of something, estimate the and ignore one-third. If you do not, then leave (at least) one fourth.’ Related by the five Imams, except for Ibn Majah.”
Bulugh al-Maram 726, Book 4, The Book of Zakah, Hadith 20. 1 min read