Answer
Wa `alaykum as-salamu wa rahmatullahi wa barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
1- Zakah is the third pillar of Islam. It is considered a purification of wealth, and it is always related to prayers in the Qur’an; whenever you read (…Perform prayers…) in the Qur’an, it is followed by (…pay Zakah…).
2- It is also known that Zakah has special rulings concerning its time and amount of money. It is due when a Muslim owns the minimum amount due to Zakah (called Nisab), and is paid every lunar (hijri) year which is known in the Islamic Fiqh as hawl.
In his response to your question, Prof. Dr. Monzer Kahf, Professor of Islamic Finance and Economics at Qatar Faculty of Islamic Studies, states:
The rule is to begin a year from the first time one has the nisab (the minimum zakatable amount of money). Once you determine your hawl (lunar year) by this criterion, you just go to the end of hawl. That is after 354 days and pay Zakah on all the money and other Zakatable items regardless of the date of each addition.
Don’t you notice that the Zakah officers at the time of the Prophet (peace and blessings be upon him) used to include all newborn camels and sheep in the total amount, even though they may be newly born?
Allah Almighty knows best.
Editor’s note: This fatwa is from Ask the Scholar’s archive and was originally published at an earlier date.