UK mobiles in the US
me and my friend are travelling around the states for 3 months-was wondering what the best thing is to do with regards to using our mobiles over there-dont see much point in getting a CB radio cos we're gona be using the trains a lot as well as car rentals sometimes.
It's a Throwaway World
Your mobile phones will almost certainly not work over here. Not only do Europe and the United States use different frequencies, but they use different technologies as well. It may be possible to swap out some chips/cards in your current phone so that it will work in the US, but I doubt it. What you can do is buy a relatively cheap 'disposable' phone once you get here. These have limited features and are good for only a limited number of minutes, but you could probably get one for about what a full featured phone would cost for a month's service.
Hmm.. check with your mobile phone company
The US has recently started moving to a GSM cellular phone standard, over the last couple of years. What AZBuck says about US cellular phones is true in general, but with the new GSM cellular phone standard coming into use there is the possibility of "world phones" -- that is, a phone that can be used in Europe and the US. I've used a US-bought cell phone to place calls in the US and Europe with the same phone. But it is not common at all.
While I've seen and used these in both California and Europe (Italy and France), they require a specific SIM card setup, which I do not believe is standard. I know you can request this option for phones bought in the US as a priced option, and I suspect that using a UK bought phone in the US will also require a specific set up of your SIM card.
Check with your mobile provider, and I'll wager they have a US partner and will be able to set up your SIM card for use in both the US and the UK and Canada. It won't be as cheap -- in general, US cellular rates are very high compared to the EU, plus you'll have the international access charge as well. This isn't possible for all phones (the US GSM standard is slightly different from that in Europe), but I've seen it done.