Which cellular services use SIM cards on phones?

I want to use my Sony Ericsson phone on a different network, by swapping the SIM card. Which service providers use SIM cards?

Which cellular services use SIM cards on phones?
Hi there,





SIM cards are used by GSM providers. In the U.S., the major GSM providers are AT%26amp;T (formerly Cingular) and T-Mobile. There are also smaller regional providers that use GSM as well depending on where you live. CDMA providers such as Verizon, Sprint, Alltel and U.S. Cellular have networks that are not compatible with phones that use GSM and SIM cards.





Hope this helps!
Reply:Another thing to consider is, most cell companies lock the phones to their network so changing to another network you may need to get the un-lock code for your model phone. Good Luck..

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