Before your rush out and buy a phone card (especially those of your who have never used one), there are a few things to keep in mind. The following phone card advice will give you the basic information you need to select the right phone card for your specific calling needs.
Phone Card Advice:
Compare Phone Cards - There are many considerations to include in your purchase decision (rate, fees, guarantee, expiration date, quality, etc.).
Review Rates - Keep in mind that the lowest and highest rates are not always the best and worse (respectively). Fees can have a huge impact on the final rate and ultimately the amount of minutes you receive.
Look for Additional Fees - In many cases buying a phone card with fees is a good decision. Since many carriers deduct fees after the first hang-up you can avoid them by using all available minutes on one phone call, thus getting the best possible rate.
Compare Expiration Dates - This is important if you intend to purchase a phone card to use at a later date or decide to leave minutes on it to make multiple calls.
Look for Guarantee & Return Policy - Finding a phone card retailer that offers a guarantee and a clear return policy is important. Many do not offer a guarantee or a clear return policy, which means you could be stuck should any issues arise with your phone card.
Consider Your Specific Calling Needs - If you intend to make many shorter length calls (leaving minutes on your card), consider a phone card with little to no additional carrier fees. If you intend to make long calls and can use a card in one call consider a card with a lower rate, but be sure you use all of the minutes or they could be quickly depleted by any carrier-based fees. Phone cards come available in many denominations (values) to help fit your calling needs and budget.
We hope to have dispelled the belief that making an international phone call from your cell phone is expensive. Millions of people use phone cards every year to make international calls from their cell phone while reducing their costs by up to 95% on every call. Further, technology today is such that you can use a phone card to make an international phone call from your cell phone without sacrificing calling convenience. Your next call should be clear. Use the rate finder above to find the right phone card for your calling needs.
If you have any questions about prepaid phone cards, please feel free to contact us or browse our frequently asked questions. You can also reference these articles, “Tips for Finding the Best Prepaid Phone Card for Your Needs” and “Top 5 Prepaid Phone Card Benefits.”
Note: Check with your cell phone provider to see if you can use prepaid phone cards to make international calls from your cell phone.

Source: http://speedypin.com/phone/card/articles-cell-users-cut-international-calling-costs-phone-cards.html