> Apparently in 40 states as of Jan 27 2013,
>retailers can charge up to a 4% surcharge.
Whether the law allows or disallows credit card surcharges by the
merchant, it makes little difference because there is already
contractual ban on merchants surcharging the use of credit cards, if
they accept mastercard, visa, american express, or discovercard.
Some merchants ignore the merchant contract, and surcharge anyway.
Often they do this if a min purchase price is not met. It is against
their contract, and you can report it to visa, mc, amex, or discover
if you catch them doing it. But they tend to get away with it because
the credit card companies do not enforce the contract.
If a merchant wants to get around that, they are permitted to have a
lower cash price, but it cannot be advertized as a discount on
everything with one sign. IIRC, they must mark a separate cash price
on each item that has the cash discount. That's not law, just what's
in the visa merchant agreement.