AT&T
As a GSM carrier, AT&T (formerly Cingular Wireless) offers a comprehensive global network. You generally can roam from Canada down through Argentina; throughout Europe, Asia, and Australia; and in various African countries. Coverage is also available in Japan and South Korea, but you must have a phone that operates on the 3G band of 2100Mhz. AT&T sells compatible handsets, or you can rent a phone equipped for those countries' networks. Coverage also extends to some cruise ships. AT&T sticks you with per-minute roaming charges, and you'll have to get your international roaming activated, but you're not liable for any long-distance charges. The carrier offers a selection of compatible phones, and if you manage to unlock your mobile, you can use a prepaid SIM card.

Frequent travelers can sign up for the AT&T World Traveler plan, which gives you a discount on most roaming rates in more than 195 countries for $5.99 per month. For travel closer to home, AT&T Canada offers a standard 59-cent-per-minute roaming rate for $3.99 per month, while AT&T Mexico offers the same rate for $4.99 per month. On the data side, the Unlimited BlackBerry International plan lets you receive unlimited e-mail for $69.99 per month. iPhone users have two plans available. For $24.99 per month, you can get 20MB of data in 36 countries, or for $59.99, you can get 50MB of data in 36 countries (see AT&T for a complete list). For Windows Mobile and Palm device owners, $24.99 will give you 20MB of data in the same 36 countries.

 * Varies by country and by international roaming plan.



The green areas indicate where you can use an AT&T world phone abroad. For a complete list of rates and coverage, visit AT&T's Web site.

World phones include:

Sony Ericsson W580i Apple iPhone

Samsung BlackJack Motorola Razr V3

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