This is why some companies don’t take certain credit cards.
Credit cards are only “free” to the consumer. The merchant actually has to pay a fee, usually around 3% of transactions. You can pay this per transaction, or you can pay by batch. (a list of transactions, all done at once every day.)
So if you take say $10,000 in sales, the credit card companies are going to charge you roughly ~$300 in fees.
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