If we’re talking your standard merchant here—say, a grocery store or clothing retailer, then they don’t have a “direct way of finding the amount of available credit or credit limit on someone’s card,” says John Ganotis, founder of CreditCardInsider.com.
“A merchant could, however, submit a pending charge to make sure there is enough credit available to cover a purchase,” says Ganotis. “If the pending charge fails, the merchant knows there’s not enough to cover the amount, although the merchant doesn’t find out the exact amount of credit remaining.”
He notes that this is typically what happens at gas stations. “When you insert your card at the pump, the gas station will usually put a $50 or $75 pending charge on your card to make sure the card has enough available credit to fill up most cars,” he says. “After the transaction is done, the gas station will finalize the transaction with the actual amount. Sometimes it takes a few days for the finalized transaction to show up.” Hotels and rental car companies do something similar.
Matt Schulz, Chief Industry Analyst at CompareCards, adds, “if you’re buying something, the provider would only know if you have enough to cover the purchase or if you don’t.” They won’t know exactly how large (or small) your credit line is.
Greg McBride, chief financial analyst at Bankrate, says it’s unlikely that a third party could have up-to-the-minute information available to them. But “on a lagged basis, it is possible, particularly if the service provider has run a credit check as they can look at the credit report and get an idea of what the available credit was as of the most recent reporting to the credit bureau.”
So it’s not likely that your current available credit or account balance will be disclosed, as least legally, without your consent. “That being said, such information could possibly be obtained through nefarious reasons so its not impenetrable, just like anything else,” says McBride. But if you don’t want your local gas station knowing the ins-and-outs of your credit details, don’t worry about it.