What is the quantum of nisab upon which zakat is to be paid?
In the name of Allah, Most Compassionate, Most Merciful.
Zakat is compulsory upon a person who possesses the quantum of nisab (i.e. 612.35 grams of silver or 87.47 grams of gold or currency, wealth equivalent to that amount) for a complete lunar year; which is over and above his basic needs and also free from debts. (Raddul Muhtar Vol 2, P5)
Therefore if an individual has in his possession wealth which is free from his basic needs and this amount after deduction of liabilities exceeds the quantum of nisaab then it will be compulsory to pay zakat (2.5%) upon passing of a complete lunar year.
(The nisab in monetary terms can be obtained by getting a quote of the current gold prices from your local jewelers.)
And Allah Knows Best
Darul Ifta Birmingham