Not sure about which calling card to choose? Confused with all the complex math that goes into calculating your calling rate? Read on for a step-by-step approach to help you choose the best calling card for you.

1. Research the card of interest to you. Before purchasing, it is a good idea to check out the "details" link next to the card of your choice.

2. Study the rate offered.

When you choose a very cheap prepaid phone card, it is usually associated with more hidden charges. You need to pay attention to several common hidden charges, or the card can turn out to be a lot more expensive than you bargained for.

Following are the common hidden costs you need to look for:

• Connection Fee: Also called first-minute surcharge. A connection fee is the additional fee imposed by the telephone company every time you use your phone card to make a call. It varies between 25 cents to as high as $3. Connection fees add tremendously to the per minute cost of the call. If you encounter a call drop and have to redial the number you will be charged connection fee all over again.
• Disconnection Fees: Be wary of disconnection fees, which work pretty much the same way as connection fees but are charged when you hang up. Also known as hang up fees.
• Maintenance Fee : Maintenance fees are deducted from your card without you even making a call! These fees are assessed on a monthly, weekly, or even daily basis. Some phone cards will start charging a maintenance fee either when the first phone call is connected or after the first phone call is finished. It could be as high as $1.50, so check it out, too.
• Communication Fee: Certain phone cards charge a communication fee up to 25 per cent of the phone call's cost. This makes the rates to be 25 per cent more expensive in reality. The advertised total minutes looks more attractive because this fee is usually applied after the call is finished.

Long Talking Fee: Certain phone cards charge this fee that's rarely known to lots of customers. If the customer talked for more than 20 minutes, 40 cents will be charged for every 20 minutes talking time. This equals to 2 cents more per minute.

Multiple Minute Rounding: Multiple minute rounding means you pay for more minutes that you actually spoke.

For example, if you spoke for six minutes, some cards will charge you based on "5 minute rounding" and charge you for a 10-minute call! This brings your effective rate per minute up, because you must calculate paying for those added minutes that you did not use! Industry standard is one minute rounding, as in the case of your residential telephone services.

3.  Consider where you are calling to. Most of the calling cards offer different rates for different cities. Also they have different rates for calling to a landline or a wireless (mobile) phone. You would often find people carrying five-six calling cards on them to call to different cities.

4.  Connections:  Many calling card companies use VOIP circuits (poor quality). These are generally of poor quality. Often calls will have intolerable delays, missing words, and sudden disconnections.

5.  Choose a provider you can trust. Many of the ultra-cheap calling card companies disappear overnight.   You don't want to be stuck with a worthless piece of plastic, nor do you want to give your credit card number to a company that is barely staying in business.