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I own two phones and I want to be able to use both of them with my service provider (but only one at a time) without paying for two separate lines. I assumed that the SIM card was the hardware AT&T used to keep track of phones, but I have also heard they might use something called a Universal ID Code. Is it possible to use both phones? And if I can, would it be legal?

jon
2011-10-27 23:20:00
do you mean switching  the sim between both phones?
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Mike
2011-10-06 06:21:00
The alternative to SIM Cards in the US would be CDMA (Code Division Multiple Access) at which a phone is somewhat programmed for a specific provider.For SIM card based operators you obviously can use both phones since you can always put the SIM card into the other phone. If you don't want to do this step you would need a second SIM at which point it is all up to your provider whether it's possible or not. Usually a provider will only give out one SIM card per line to a customer and if you go about to order a new one (e.g. saying you lost the other one) they would deactivate the old one.So unless they are willing to give you two operating SIM cards you probably have to either pay for a second line or switch the card between the phones.As for CDMA phones it is pretty much the same. I don't know the exact way but basically your CDMA phone and your network access are bound to each other. If you want to switch device the provider will usually deactive the old one for network access and associate the new phone to your contract.I'm not sure if it is technically possible to have two phones on one contract but it's safe to say you do have to contact your provider in any case to gain network access with another device.