Expert: Roberto Serrano - 9/21/2008

Question
Let me see if I understand Verizon phones with SIM cards.....the phones actually work without the SIM card here in the US but need the SIM card to work overseas.  So, does that mean that if I put the Verizon SIM card in an unlocked phone here in the US, the phone won't work? Verizon seems to be behind other cell carriers when it comes to SIM technology. Thanks for your answer and time!!

Answer
Hello Sid,

I believe you have this mixed up let me see if I can clear things up for you.

Verizon phones use technology called CDMA
At&t phones use technology called GSM

CDMA phones are programed by there ESN number electronically these do not need or require a sim card to work.

GSM phones are programmed by there IMEI number electronically these need an sim card in order to work.

Verizon does not carry phones that use sim cards you would need a GSM phone for a sim card phone.

If you want to purchase a phone to go overseas you need an Unlocked GSM quadband phone.

I hope that I have been of help to you if you have any other questions please do not hesitate to ask. Thank you for your question.