Why Doesn't My Cell Phone Work Outside My Home Country?

Wireless phones have become the norm for lots of you—probably even most. And as long as you stay in your phone's home country or region, wireless poses very few problems. But keeping wireless service overseas can be more of a challenge. A reader, obviously facing difficulty, recently asked:

"Is there cellular phone service that works in both the U.S. and Europe? I have VodaphoneUK, but my phone doesn't work when I travel here. Is there a way to make it work, or is there a service that works in both locations at once?"

Although this reader's question applies to the minority of SmarterTravel.com visitors who live outside North America, the mirror-image dilemma—using North American phones overseas—is also an issue for many U.S. and Canadian residents. In either case, the short answer is "yes, some services work in both North America and Europe, but not all." Getting service abroad involves technical questions about both your wireless provider and with your phone.

The Right Technology

The first key to interoperability is having a phone that uses the GSM wireless system—it's the only one that works in both Europe and North America. Although almost all European wireless systems use GSM, not all North American wireless systems do. If your service is with any main European provider, or with a North American phone company on the GSM standard (AT&T, T-Mobile, and a few others), you're using GSM. But if your wireless service is from a company that does not use GSM, your only recourse for overseas calls is to buy or lease a GSM phone for temporary use.

The Right Band

Even if you have a GSM phone, however, interoperation requires more. Your phone must also operate on the right bands. The GSM system uses four different frequency bands, two in use in North America and two different ones in Europe. If you want to use the same phone in both regions, it must be either a three-band or a four-band model. Many current model GSM phones do have three- or four-band capability, but not all. If yours doesn't, you need to exchange it for one that does.

The Right Card

The final hurdle to full interoperability is activating your phone for overseas use. Here, you have two basic options:

• If you want to keep your regular wireless phone number overseas, get your phone company to activate your account for overseas use. That may require installing a different SIM card—a small permanent memory card that retains the important data about your account. This is a convenient option, but outgoing calls from a different region are apt to be very expensive, and even incoming calls typically incur a heavy charge.
• For minimum cost, sign up for a separate local service in each region where you travel. Typically, you can find services that offer very low outgoing rates and often no-charge incoming calls. To do this, you need to get a separate SIM card for each region. That means using a different phone number with each card.

The Unlocking

When you first got your regular GSM phone, it was probably "locked," meaning it did not accept foreign SIM cards. A retail office that handles phone sales for your regular service provider may be willing to unlock your phone; if not, lots of independent wireless phone stores do it for a nominal one-time fee.

Costs, Convenience, and Sources

I reviewed the various overseas calling options—from the viewpoint of North American travelers heading overseas—in an earlier answer. However, much of the information there applies equally to visitors from other areas traveling in North America. And the information about relative cost and convenience features is still relevant in either case.