Do Gas Stations Need Your Zip Code?

Recently I was buying gas at a gas station. I was paying with my credit card and the machine asked for my zip code. If you read my previous post, you know what happened: I got furious. First, I tried 00000 as a zip code. The machine was smart enough to tell me that it was invalid. No matter what combination I tried, it wouldn’t accept another zip code.

Finally, the machine got frustrated with me and printed on its screen that I needed to talk to the cashier. Then, I argued with the cashier. He could have suggested that I pay cash, but he didn’t. I left without gas.

Luckily, for me I had dinner that day with my son, Alexey Radul, and his friend, Grem. Grem explained to me that gas stations are not collecting customers’ zip codes. They use zip codes as a security measure for checking that the credit card is not stolen. I guess that means I behaved exactly like a person who stole a card. Protecting your own privacy sometimes makes you look like a thief.

After dinner, I went back to the same gas station to conduct some experiments. This time I was armed with several valid zip codes. It didn’t work. Grem was right — only the zip code corresponding to the card could have worked. I looked like a thief again. I paid for my gas with cash and left.

The next day I called my credit card company and asked them about this. The manager I talked to told me the same thing as the manager Grem talked to. Apparently credit cards do not give your zip code information to gas stations. Your zip code is used instead of a pin number to verify that your credit card is not stolen. So in this case you do not need to worry that you are providing extra information, since credit card companies know your zip code anyway.



  1. Aaron Wakling:

    I found your site on technorati and read a few of your other posts. Keep up the good work. I just added your RSS feed to my Google News Reader. Looking forward to reading more from you.

    Aaron Wakling

  2. Grem:

    It is, in fact, illegal for your gas station to collect your zipcode information themselves:

    I imagine the credit card company provides aggregate zipcode info to the merchant anyway.

  3. Sammiry:

    favorited this one, bro

  4. Harry:

    It is very difficult for a Canadian to put in a zip code. I do not buy gas at those stations. They must lose buisness.

  5. Jesper:

    As a tourist in the US, I also have troubles every time I want to buy gas. If I’m lucky I can “cancel” the zip code question, but during the last few days (since I entered Florida), this is no longer possible. I’m from Denmark and for some reason I can’t use my card as a debit card either, since the pin code verification promptly fails outside Europe. This is making a simple task of buying gas so frustrating and painful because I no longer can fill up the car, I have to estimate how much gas I need and how much it will cost. If I gas under the estimate that money is either lost or at very best I need to see the cashier twice per buy. I also travel with a spare canister of gas in the trunk, because I don’t want to be standing in the middle of nowhere a rainy dark night as a closed gas station.

    The zip code verification sucks big time – at least they could make up a special code for foreign credit cards or just make the debit system work internationally.

  6. john d:

    RE: zip codes at gas stations.

    This new security procedure is designed to save us all money by assisting to control credit card costs due to fraud…millions per year. It’s not the complete solution but it is one more step. The mega-credit card companies that monopolize the card industry pass much of the fraud costs down to the retailer in the form of fees and transaction chargebacks and of course those costs have to end up in the price of the consumer goods.

    By the way. I hope you returned to the station to apoligize to the minimum wage clerk whom you vented on!

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