It is often compared to the system of tithing and alms but unlike these older systems, it serves principally as the welfare contribution to poor and deprived people in the Muslim lands, although others may have a rightful share. It is the duty of the state not just to collect it; but to distribute it fairly as well.
Zakat is one of the Five Pillars of Islam.
Zakat is not mandatory on harvest if the total did not reach the minimum limit of about 653 kilograms , nor on gold amounts if the owner has less than 85 grams or silver less than 595 grams
إِنَّمَا الصَّدَقَاتُ لِلْفُقَرَاء وَالْمَسَاكِينِ وَالْعَامِلِينَ عَلَيْهَا وَالْمُؤَلَّفَةِ قُلُوبُهُمْ وَفِي الرِّقَابِ وَالْغَارِمِينَ وَفِي سَبِيلِ اللّهِ وَابْنِ السَّبِيلِ فَرِيضَةً مِّنَ اللّهِ وَاللّهُ عَلِيمٌ حَكِيم
"Alms are only for the poor and the needy, and the officials (appointed) over them, and those whose hearts are made to incline (to truth) and the (ransoming of) captives and those in debts and in the way of Allah and the wayfarer; an ordinance from Allah; and Allah is knowing, Wise."
People whose hearts are to be reconciled include (normally new Muslims or those close to becoming Muslim. Non-Muslims cannot be included):
There have been cases where you can't pay zakat for
In all the four recognised madhhabs the fiqh of Zakat is very much the same with the key elements that make Zakat compulsory for an individual being: Islam, Freedom, the Nisab, Ownership and a Year's Possession.
Therefore, it should not be looked at as being only an economic duty..
An example calculation of the Khoms tithe: A man starts with $5000 in his bank account; on the same day after one lunar year passes, he has $5600 in his bank account (having already paid his bills and debts), and so must take the fifth of his $600 earnings, that is $120. What remains after the fifth (that is $5600-$120=$5480) is recorded; if after one lunar year the man has more than $5480, then he finds the new difference and extracts a fifth from it as before. If instead he has less than $5480, then he has no earnings on which to pay Khoms. The Khoms is paid specifically for:
Zakat on the other hand, according to the Shi'ite teachings, is assigned to specific goods. There are nine types of goods from which Zakat is paid out: gold, silver, camels, cows, sheep, wheat, barley, dates, and raisins. Each type has its own "nisab," or a limit under which Zakat need not be paid. Zakat is paid to the people mentioned in the overview of this article, although never to a Sayyid. Charity money or Sadaqah is never to be paid to a Sayyid since it is a taboo for a Sayyid to take such money, if it is not Khoms or a gift. Notice in that in both concepts, they are obligatory on the individual but should not be forced by the governor.
In modern days, Shi'ite Muslims are concerned with Khoms more than Zakat mainly because few of them are farmers and own the goods by which Zakat is paid out. On the other hand, Khoms is given by many people starting from the middle class and above that, and especially by employees.