But a Consumer Reports investigation finds it's buyer beware.
Mary Meza uses phone cards to call her family in the Dominican Republic. But she complains she doesn't always get as much calling time as she expects.
"I get really angry because I think it's not fair," she said.
Consumer Reports analyzed more than 130 prepaid phone cards. Most cost just $2 to $5 and look like bargains. But Consumer Reports found lots of problems.
"Three quarters of the cards we looked at didn't tell you how much it cost to make a call," Consumer Reports' Robert Tiernan said. "You usually never found out until you were on the phone."
And Consumer Reports found the amount of calling time varies tremendously. For example, two different cards each cost $2, but one gave 200 minutes to call Mexico City. The other, just five minutes.
And there can be lots of fees, which may be listed on the back in tiny type. Those prepaid phone card fees can include a fee for connecting or disconnecting or calling on a cell phone or calling from a pay phone. There can even be a daily maintenance fee.
"The fees can really eat into the value of the cards," Tiernan said. "These were completely drained before we ever made our international call."
In some cases, Consumer Reports was able to get the fees reversed, but only after calling customer service.
"If you frequently make calls overseas, there are better alternatives," Tiernan said.
You can use Skype on your computer or smart phone to call overseas for modest rates, which are clearly spelled out on Skype's website.
And if you and the person you are calling both have Internet, the call can be free.
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