Why do cashiers ask for your zip code

At one point I actually thought this information was necessary to complete my purchase. It is not. As it turns out, your zip code can lead to more than that. When you swipe a credit card at the cash register, the merchant receives your name, card number and expiration date, but little else. The Stir 's April Daniels Hussar says not only do stores use your ZIP code so they can market to you, but also they can sell your information to other companies.

I have since replied with a polite, "no thanks" when asked for my ZIP code. But be aware that a credit card issuer sometimes asks for that information. American Express, for example, may prompt you to key in your ZIP code at some stores for security purposes. The information is not kept by the merchant and not used for marketing, the company says. And you do still need to provide your ZIP when shopping online, whether to indicate where to ship your stuff or as part of the Address Verification System AVS online merchants use to fight fraud.

Many gas stations use a similar method during pay-at-the-pump purchases. Email us at consumernation cnbc. Privacy Advocates Say No. Trying on clothes is tedious, and sometimes completing the actual purchase is, too.

I just want to pay and be on my way, and they give me the third degree. I always decline to give my e-mail address, since the last thing I need is more promotions clogging my in-box. It turns out, though, that stores are asking you for marketing purposes — an issue that is starting to come to light in state courts.

Stores want your ZIP code because, combined with your name from your credit card, they can use it to find out other information about you from commercial databases, like your full mailing address. The process costs money, and unless they have a way to market off the data, there would be no reason to do it. She said they do not cross reference names and ZIP codes with other data, but just try to understand where their visitors are coming from. This is a BETA experience. You may opt-out by clicking here.

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