How would consumers who traditionally pay using cash potentially benefit from an interchange fee cap?

Interchange fees increase the cost of selling a good or service. For example the interchange fee for using a credit card in the US is around 2%, so the cost of selling a good or service using a credit increases by 2%.

If a cap is set on interchange fees, then they should probably decrease, decreasing the cost of selling goods or services. For example, in the UE the interchange fees are capped to 0.3% for credit cards and 0.2% for debit cards.

Since the cost of sales using debit and credit cards would decrease, the price of goods and services should also decrease. If the interchange fees are extremely low, then all businesses should adopt debit card and credit card payments as equal to cash payments.  

This will probably lead to more cash paying individuals deciding to use debit cards, and maybe even credit cards.

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