Americans like their plastic. According to a Federal Reserve Bank of Boston study conducted in 2014, 72 percent of all U.S. consumers carry at least one credit card; a Gallup survey indicated that the average credit card holder owns close to four cards.

While this is good news for convenience, travel, and building a respectable credit score, not all card issuers are looking out for your best interest—literally. Take a look at some of the terms and conditions that can turn a useful tool into a raw deal.

1. YOUR DATA MAY BE SHARED.

Your credit card issuer knows quite a lot about you, and not just privileged information like your social security number. They can pull a wealth of data from your spending habits—amounts, retailers, time of day—with incredible accuracy. If your agreement indicates the company is allowed to share that with third parties, those businesses can in turn bombard you with marketing materials. Make sure you understand how you can keep your spending habits to yourself: Companies usually have a method for you to request they keep your profile private.

2. THEY CAN KEEP PULLING YOUR CREDIT REPORT.

Card issuers like to keep themselves updated on who they’re dealing with, and a credit report remains the gold standard in revealing a consumer’s financial health. If you’ve agreed to their terms, you may have granted permission for them to check your score on a periodic basis. Those inquiries can have a negative impact on your score. And if your score has dropped since you first applied for the card, the credit card company could increase your interest rates or lower your credit limit.

3. YOU COULD HAVE ALREADY AGREED TO ARBITRATION.

If a dispute over your balance arises and you think you can address the disagreement in court, think again. Many credit card agreements require the consumer to agree to arbitration with the issuer, which is a private negotiation that may not be settled in your favor. See if you can opt out by sending in the requested paperwork.

4. YOU COULD BE LOOKING AT A SERIOUS PENALTY RATE.

Credit card offers like to use provocative zero-interest introductory offers or low fixed-rate terms to attract applicants. Less advertised: what happens if you miss a payment. Banks can turn that generosity into a hassle if you make a late payment on your balance, with some penalty rates soaring up to 32 percent. While it’s best to look for a card without a penalty (also called default) rate, make sure you know what the issuer expects you to do—typically six consecutive on-time payments—in order to cure the situation.

5. WATCH OUT FOR CASH ADVANCE FEES.

Borrowing against your credit line for cash dispensed at an ATM is a financially punitive situation. In addition to the ATM fees, your card is going to hit you with other surcharges that can add up. The interest rate is also often much greater than if you had used the card for a purchase—up to 24 percent—and a cash fee of 5 percent or more is added on top of that. If you took out $500, you’re out an extra $25 immediately.

It gets worse if you only take out a small sum, as some cards have a minimum $10 cash fee. For $50, that’s really 20 percent. Check and see what your card is asking for before taking any money from a machine.

6. THEY CAN DISGUISE THEMSELVES.

One card issuer got some unwelcome publicity in 2014 when it was discovered that their card agreement allowed for operators to phone card holders without having to identify themselves on a Caller ID device in select states. If you'd prefer to know who's calling, make sure your issuing company doesn't hide behind spoof numbers.

7. DEFERRED PAYMENTS ARE A MINE FIELD.

Taking a promotional offer on a card that offers zero percent interest for a fixed period of time can seem appealing, but a closer look at the terms usually reveals an unfortunate consequence: owing even a small fraction of the original balance can mean interest is charged for the full amount retroactively. Additionally, making a promotional purchase and then a “regular” purchase on the same account can confuse which debt you’re paying down when attacking the balance. Make sure your lender isn’t redirecting funds or leaving you with a lump sum of interest.

8. IT MIGHT BE SECURED DEBT.

When you take out a loan for a home or car, your lender has some protection against a default: Don’t pay, and the wheels and house might wind up becoming theirs. While credit cards are considered unsecured—meaning banks have no recourse other than slamming your credit report and hitting you with fees for non-payment—some have taken to insisting upon a security interest in any goods purchased. That means you’ve agreed to let them seize your belongings for defaulting. While it’s unlikely for a small item, buying a whole new set of kitchen appliances could be cause for someone to come knocking.

All images courtesy of iStock.