Will I be able to use my UK mobile in the US?

It’s a Samsung D500, purchased in the UK. (It’s also unlocked).

There’s an option on it to change the band, and there are three choices: GSM 900/1800, GSM 1900, and Tri band. I’m fairly certain that one of these is the US standard. does that mean that, when I return to the states (and assuming I can find a way to get at my US SIM card), my phone will work there?

Yes. Although I’m not sure what you mean by “900/1800, 1900 and tri-band” - Tri-band is just the name for a phone that can operate on three frequncies: 900MHz and 1800MHz (used in Europe, Asia and Africa), and 1900MHz (used in N America).
There are also “quad-band” phones, which also include 850MHz which I believe is also used in America. But your tri-band phone should work in the USA.

The US standard is 1900 MHz; some areas operate at 850 MHz but I think it’s in more remote areas. Where will you be using the phone?

I’m not sure what the choices mean on your phone because I thought that Triband meant it will support 900, 1800, or 1900. Maye Triband is an auto-detect mode.

My mother in law did this. When she went to Europe, she went to a local shop, bought a prepaid sim and she was good to go. There was really no mystery to it.

In the U.S. Cingular sells prepaid Sims so that should work with your phone. The power adaptor may be trickier though.

Most triband phones are auto-detect, so you shouldn’t have a problem. You might have a problem if you go somewhere without a GSM network though.

Your phone’s GSM-1900 band will work in the US, but rural coverage may be lacking.

Listing of US GSM companies with coverage maps, from the GSM Assocation. Most of these seem to small local companies that may not have roaming agreements.

The big US GSM companies include Cingular and T-Mobile. (I could have sworn AT&T was in there somewhere, but the corporations ave merged and unmerged and renamed themselves and split and bought each other up for so long that I have totally lost count of who’s who anymore.)

More info…

GSM frequency ranges, from Wikipedia.

My cellphone company’s GSM frequency-usage maps of the world.

The Americas are a patchwork of all four GSM cellphone frequencies.

GSM-1900 is common in the US and Canada, and also scattered other parts of the Americas that have been under US technical influence. The US, Canada, and several other countries also use GSM-850, which is replacing the GSM carriers’ legacy analogue cellphones in rural areas.

A few American countries use only GSM-850: Panama, for instance.

Areas under ‘European’ influence, such as the French overseas territories, tend to use the mainline GSM frequencies (GSM-900 and 1800).

Brazil uses GSM-1800. Venezuela uses GSM-900. Peru uses 1900 and 850, I think.

Some Caribbean islands use a mixture of parts of all four standards. I’m still trying to figure that one out, especially since GSM850 overlaps GSM-900 and GSM-1900 overlaps GSM-1800.
I avoided the whole problem and bought a quad-band phone. :slight_smile:

Auto-detect sounds most likely; I wondered about that myself.

I’ll most likely be using it primarily in the Santa Fe (NM) area; coverage there tends to be spotty no matter what network you’re on (fairly rural, for one. Big mountains in the way, for another).

Pretty much the only reason I’m even interested is because up until this past spring, I was on my parent’s ‘family plan’ contract back home. I believe it was renewed without me being on it (as I was out of the country), so I may be looking for a new network. If I can do it the UK way (eg, pick a network, say, “Hello, I would like a sim card with $20 on it, thank you.”, pay $20, and get on with it), it would greatly simplify my life.

Probably not. Nearly all power adapters for phones and computers work on both 110VAC and 220VAC. I have a UK GSM phone (low-end Motorola) and I have used the adapter both in France and the US.

It’ll work fine. My girlfriend took a Samsung D500 to New York earlier this week and it worked fine. You should check with your provider that there’s no international block on calls, and it’s always worth checking the charges on your provider’s website before you travel (paying for incoming calls can be a lot of fun).

Yeah, I believe that Cingular and T-Mobile let you do this. I looked at the coverage map for Cingular and it is strongest on the East Coast and looked pretty sparse away from the coasts.

If you are moving back to the U.S., it might be best to wait until you come back and get a phone where you are going to be living.