In applying for a zero interest credit cards, the most important thing to keep in mind is that all such cards are not equal. In nearly all cases, the zero interest credit offer is simply an introductory rate. This means that, the credit card company will charge you no interest for a specified period. But after that introductory period is over, their "real" rate will kick in.

In other words, the main things that anyone accepting a zero interest credit cards offer should look for is the fine print which details what the interest rate will rise to once the introductory period is over. Only then can they be assured of having enough facts to make a truly informed decision.

Consumers signing up for zero interest credit cards need to be aware of the potential pitfalls. It's no secret that credit card companies are in the business of making money. And they make money by charging you interest for the privilege of using their card to buy things. So how exactly can a credit card company possibly make money by offering you a credit card on which you pay not interest? The answer is that they can't, unless they make up the money some other way.

And that's why it's important for you to read the fine print in the offers for zero interest credit cards. If you physically cannot read fine print, it's well worth your while to visit the local pharmacy and purchase a magnifying glass or a pair of reading glasses to help you with that "fine print" thing.

Zero interest credit cards will always come with a built-in "nullifier" which negates the zero interest deal if the credit card holder violates certain terms of the agreements. These terms are partially meant to provide a degree of protection for the credit card company. But they're also formulated and written to provide extra income to the credit card company 

These companies fully realize that most people will never even read the full terms of the agreement. They further realize that the terms are written so that a significant number of people who sign up for the card will unknowingly violate one or more of the terms thus giving the company a legal out to nullify the zero interest rate on the credit card.

Another thing to watch out for on a zero interest credit card is the existence of an annual fee. Many times the fee won't be charged at the outset, so you'll never know there is a fee, unless you read the fine print. But at the end of the year, a fee for your no interest credit card will suddenly appear on your credit card statement.

The fact that a credit card company charges a fee is not bad in and of itself. In fact, you may decide that the fee is worth having a zero interest credit card. It's only bad if the company is not upfront with you about what all the fees are and attempt to hide them in the legal speak on the application.

Another zero interest nullification fee to watch out for is the over limit clause. For instance, if your credit card has a limit of $5,000 and you purchase an item with it for $6,000, you have just gone $1,000 over your credit limit. And whether you pay off the balance when the bill comes due or not, many clauses state that if you go over the limit the credit card company has the right to nullify your zero interest rate and raise it to whatever amount you agreed to when you signed up.

In recent years, many companies have heavily abused over limit clauses by charging exorbitant fees to customers that go over their limit. In some cases, the amounts charged are so egregious that they've become a defacto profit center for the credit card company.

Another of the extra "hidden" fees that consumers who sign up for zero interest credit cards encounter are excess fees for cash withdrawals. In addition to the minimum ATM fees which may be charged, some zero interest credit cards exempt cash withdrawals from the zero interest agreement. One reason why you should only use these types of credit cards for cash withdrawals in an emergency.