Is Zakat obligatory upon a disbeliever?

One of the conditions for zakat to be obligatory is that the Muslim must be a Muslim. Zakat is not obligatory upon a disbeliever. The evidence for this is the Almighty’s saying: “And nothing prevented their contributions from being accepted from them except that they disbelieved in Allah and His Messenger” (Surah At-Tawbah/54), and the Prophet’s (peace be upon him) saying in the Hadith of Mu’adh: “If they do so, then inform them that Allah has enjoined upon them zakat from their wealth, to be taken from their rich and given to their poor,” which indicates that Islam is a condition for the obligation of zakat.

If a disbeliever embraces Islam, he is not required to make up for the zakat from the years he was a disbeliever. Rather, he begins a new hawl (lunar year) from the time of his conversion, due to the Almighty’s saying: “Say to those who have disbelieved, if they cease, what has passed will be forgiven them” (Surah Al-Anfal/38).

Al-Nawawi said in "Al-Majmoo’": "Zakat is not obligatory upon an original disbeliever… And if he embraces Islam, he is not asked for it for the period of disbelief." Ibn Uthaymeen said in "Al-Sharh Al-Mumti’": "Zakat is not obligatory upon a disbeliever... because zakat is purification... and the disbeliever is impure. If he were to spend the earth’s fill of gold, he would not be purified until he repents from his disbelief." The impurity of the disbeliever here refers to spiritual impurity, which is the corruption of his belief, and nothing purifies him except Islam.