Is it permissible for an Islamic school to force the parents to buy school uniforms from one store despite the fact that uniforms with the same colors are available with a cheaper price in other stores? Is this not a kind of monopoly, which is banned by Islam?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah and that Muhammad is His slave and Messenger.

The school has no right to force the parents to buy school uniforms from a particular store as long as the same uniform which the students are obliged to wear is available in other stores at a cheaper price.

In any case, this obligation by the school is not a monopoly, because monopoly (intended here) means that the trader stocks food and refuses to sell it while the people are in need for it in order to increase its price. Some scholars included other commodities with food. The commentary of Ar-Rawdh al-Murbi’ reads, “Monopoly is to purchase goods for trade and to refuse selling them despite the demand of the people for them, and the monopolist is the one who receives a trade caravan and purchases food from them and wants to increase its price for the people, which is unfair for them. It was also said, 'There is no difference between food and other commodities.'” [End of quote]

Also, Fat-h Al-Mu’een bi Sharh Qurrat al ‘Ayn bi Muhimmaat Ad-Deen in the Shaafi’i School of jurisprudence, reads:

“It is forbidden to monopolize goods such as dates, raisins or any food that is sufficient to be given as Zakatul-Fitr; and monopoly is for a trader to stock what he had purchased at a time when the price was high not cheap, and then refuse to sell it so that he would sell it at a higher price when the people in his community or other people have much demand for it, even if he did not purchase it for this purpose, but this does not apply to what he intended to stock for himself or for his dependents or to sell it at a similar price or if he stocked the produce of his land.” [End of quote]

Allaah knows best.