What is your opinion on selling foreign currencies with a difference in amount? May Allah reward you with good?

Question:
What is your opinion on selling foreign currencies with a difference in amount? May Allah reward you with good?

Answer:
In the name of Allah, the Most Gracious, the Most Merciful. Praise be to Allah, Lord of the worlds, and may Allah send prayers and blessings upon our Prophet Muhammad, his family, and all his Companions. Selling one currency for another is called sarf (currency exchange), meaning converting one currency into another. If these currencies are of the same type, such as Saudi riyal for Saudi riyal, or US dollar for US dollar, or British pound for British pound, and the type is the same between these currencies, then two conditions are necessary. The first condition is equality in amount, so there must be no difference in value between them. The second condition is the exchange of possession of the sold item. If either of these two conditions is lacking, it becomes the forbidden riba (usury or interest). If there is a difference in amount, it is riba al-fadl (usury of excess in a like-for-like exchange). If there is a delay in payment along with equality in amount, this is riba al-nasi'ah (usury of deferment), meaning if there is a postponement along with equality in amount, this is riba al-nasi'ah.
As for when the type of the currencies differs, such as selling the US dollar for the Saudi riyal or vice versa, then one condition is required, which is the exchange of possession in the meeting place, and a difference in amount is permitted, due to the saying of the Messenger (peace and blessings be upon him)
It is clear to us from this that selling one currency for another requires the exchange of possession in all cases, whether the type is the same or different. As for the difference in amount, it is forbidden only when the type is the same, and it is permissible when the type is different.