We’ve all heard about those tri-band world phones that let you use your GSM phone all over Europe and Asia as well as the US as long as they’re using one of the three supported frequencies. Anyway, I was wondering that since all the phones (much less world phones) offered by my cell provider are not to my liking, would I be able to use a tri-band world phone imported or bought from Europe or Asia in the US.
Do I necessarily have to get one that has been unlocked?
If I do need to get it unlocked, how would I go about getting it done?
I don’t know for certain how it works in the US, but the deal here is that if you pay full price for the phone, it is not tied to any provider and you can put your SIM card in.
If, however, you get a phone at a reduced rate from a service provider, you are usually tied in to a contract for a fixed period, and even then you can’t use the phone with another provider unless you either get your own provider to agree to unlock it for you, or get it unofficially (illegally?) unlocked.
I have used a Motorola TimePort in the USA, on a roaming agreement from Vodafone, and it did work, though at >$2 per minute for any call (making or receiving), it was hardly practical. Most of these phones (even tri-band) will not work at all in Japan or Korea.
The Europe/Asia Tri-band phones should technically work in the US, as long as the cellular service provider offers a GSM service.
Unless, as hibernicus says, the phone is network locked to a particular network from which you purchased the phone. In that case you can still use the phone in the US, however, when you insert a US sim card into the phone, the phone will ask you for a Network Unlock Code. This code is supplied by the original network (the one the phone is tied to). Vodaphone once charged me 70 Pounds (or thereabouts) release the code so that I could use a Vodaphone UK locked phone in India with any GSM provider.
So if you buy a phone from anywhere, as long as it’s not locked to any network, you can use it in the US. The seller should be able to tell you whether the phone is network locked or not. Additionally, check with the US GSM carrier whether they allow you to purchase your own phone for use. Common sense says that they should, but you never know. Maybe some carrier does not sell sim cards independently and you have to purchase a phone the service.