Zakaah is due on trade goods according to the Qur’aan and Sunnah.
In the Qur’aan this is indicated by the general meaning of the verse in which Allaah says (interpretation of the meaning):
“O you who believe! Spend of the good things which you have (legally) earned, and of that which We have produced from the earth for you”
Mujaahid said: “Spend of the good things which you have (legally) earned” means trade.
With regard to evidence form the Sunnah, Abu Dawood narrated (1562) that Samurah ibn Jundub said: The Messenger of Allaah (peace and blessings of Allaah be upon him) used to command us to give zakaah from that which we had prepared for sale.
The isnaad of this hadeeth is subject to some discussion, but some of the scholars classed it as hasan, such as Ibn ‘Abd al-Barr (may Allaah have mercy on him), and it is the view that the scholars of the Standing Committee for Issuing Fatwas adopted.
See Fataawa al-Lajnah al-Daa’imah, 9/331.
Zakaah is due on things that have been prepared for trade if they reach the nisaab (minimum threshold) and one year has passed (since they were acquired).
Based on this, zakaah must be paid on the land which has been in your possession for a year; you have to determine the value of the land at the end of the year, and pay one-quarter of ten percent. So if its value is one hundred thousand (100,000) dinars, for example, you have to pay zakaah of 2.5% or two and a half thousand (2,500), and so on.,
If you have cash, then you must pay it and it is not permissible to delay paying zakaah until the land is sold. But if you do not have cash with which to pay the zakaah, then it becomes a debt that you owe and must be paid when it becomes possible to do so. If you cannot do it until you sell the land, then you have to pay zakaah from the price you receive for the land for each year in which zakaah was due.
Shaykh Ibn Baaz (may Allaah have mercy on him) said:
Zakaah is due on land that is prepared for trade. The evidence for that is the well known hadeeth of Samurah ibn Jundub (may Allaah be pleased with him) who said: The Messenger of Allaah (peace and blessings of Allaah be upon him) used to command us to give zakaah from that which we had prepared for sale.
He also said:
If land and other similar things such as houses and cars etc are prepared for sale, then you must pay zakaah on them each year according to their value, when one full year has passed. It is not permissible to delay that, except in the case of one who is unable to pay the zakaah on them because he does not have any other wealth. Then he may be given a respite until he sells it and pays the zakaah for all the years, each year according to its value at the end of that year, regardless of whether the value is more than the price he gets for it or is less that the price for which he bought the land, car or house.
Majmoo’ Fataawa Ibn Baaz, 14/160-161.