It is permissible to have exchange between the State currency and the currency of other states like the exchange between the State’s own coinages. It is permissible for the exchange rate between two currencies to differ provided the currencies are different from each other. However, such transactions must be undertaken in a hand-to-hand manner and constitute a direct transaction with no delay involved. The exchange rate can fluctuate without any restriction as long as it is between two different currencies. All citizens can buy whatever currency they require from within or outside the State, and they can purchase the required currency without obtaining prior permission or the like.

Its evidence are the words of the Prophet :

.» وَبِيعُوا الذَّهَبَ بِالْفِضَّةِ وَالْفِضَّةَ بِالذَّهَبِ كَيْفَ شِئْتُمْ «.

“and sell gold for silver and silver for gold as you please” (reported by Al-Bukhari from Abu Bakra), and it is reported from Malik b. Aws Al-Hadathan that he said: “I came saying who was prepared to exchange Dirhams (for my gold), whereupon Talha b. Ubaidullah (as he was sitting with 'Umar b. Khattib) said: Show us your gold and then come to us (at a later time). When our servant would come we would give you your silver. Thereupon 'Umar b. Al-Khattib (ra) said: Not at all. By Allah (swt), either give him his silver, or return his gold to him, for Allah (swt)'s Messenger (pbuh) said:

.» الْوَرِقُ بِالذَّهَبِ رِبًا إِلَّا هَاءَ وَهَاء «. Exchange of silver for gold is interest (usury) except when (it is exchanged) on the spot (hand to hand).” (reported by Muslim).

It is reported that Al-Bara’ b. ‘Azib and Zayd Bin Arqam used to be partners, and so they bought silver for money and a deferred payment, and when the Messenger of Allah (pbuh) heard about this he ordered them with the words:

. » أَنَّ مَا كَانَ بِنَ قْدٍ فَأَجِيزُوهُ، وَمَا كَانَ بِنَسِيئَةٍ فَ رُدُّوه «.