Credit cards have long impacted the price you pay at retailers.

Those costs were hidden for the most part, though, as merchants built the transaction costs they paid Visa, Mastercard and the rest into their pricing model.

As of yesterday, the fees are a little more obvious. Sunday was the first day merchants were allowed to charge a “checkout fee” to cover the transaction costs with credit card processors as part of a lawsuit settlement reached last summer.

Merchants aren’t required to charge the fee, and many have said they won’t. And the fees are capped at the costs of the processing fee, which ranges from 1.5 percent to 3 percent of the purchase price.

But the real issue is what the credit card companies charge the merchants for the swipe fees. There is technically no cap on what Visa and the rest can charge merchants, and given that more and more purchases are being made with credit – putting businesses that do not accept credit at a real disadvantage -- there is real concern about the future of the interchange fees.

The consumer, therefore, should not assume that just because they are paying a “checkout fee” the price of the items they are purchasing will go down. Conversely, those retailers who don’t charge a checkout fee will likely continue to build the transaction costs into their pricing models.

My guess is most merchants will continue with the hidden cost approach. Retailers are required to disclose checkout fees on the customer receipt and post signs announcing they are imposing the checkout fees on credit card purchases. By just building those costs into their pricing models they don’t have to deal with those regs or with customer blowback.

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