Is Commission Prohibited in Islam?
Question

I took a customer to a factory or store to buy a product, and the owner of the factory or store gave me a commission for bringing him a customer. Is this money (the commission) permissible?
If the owner of the factory adds a specific amount for each piece that the customer takes, and I take this extra amount in return for the customer buying this product, is that permissible? If it is not permissible, then what is the kind of commission that is permissible?
Praise be to Allah.The Standing Committee for Fatwa and Research said:
“If the factory-owner or shopkeeper gives you part of the money from each product that is sold through you, in payment for your efforts to find him customers, and this money is not added to the price of the product and that does not cause problems to others who sell the same product, and this factory or store sells it for the same price as others, then this is permissible and there is nothing wrong with it.
But if this money that you take from the owner of the factory or store is added to the price paid by the purchaser, it is not permissible for you to take it and it is not permissible for the vendor to do that, because this is harming the purchaser by making him pay a higher price.
 And Allah is the Source of strength. May Allah send blessings and peace upon our Prophet Muhammad and his family and companions.” (Fatawa Al-Lajnah Ad-Da’imah, 13/130)
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