How to get a sim card and use 3G data in the US on your mobile

February 14, 2011

Yanke Doodle Data


It’s not just the expense of roaming which makes using your mobile in the US impractical, there’s a number of reasons which make it hard. I’ve written this to explain how you can get a local sim card for calls, texts and data, but beware, even if you are roaming with your own sim, unless your phone is compatible with US networks you may run into problems.

What you need to know:

1. In the US they use different network technologies

In the US only AT&T and T-Mobile support GSM/3G(UMTS). The other major carriers, Sprint, Verizon and MetroPCS use incompatible CDMA technologies and only a tiny handful of dual-mode phones support both.

2. In the US they use different frequencies, so your usual phone may not work (or have no 3G access)

The two GSM operators, AT&T and T-Mobile support different frequencies for GSM and 3G services as used in most of the rest of the World. So you need to check if your phone will be compatible with their 3G frequencies, otherwise you’ll most likely be stuck on GSM/EDGE (slow).

In most countries GSM is on 900 or 1800, and 3G is at 2100. Many 3G phones bought outside of the US will therefore not work at all in the US. Confusingly the phone manufacturers often sell separate European and American versions of the same phone, but with different frequencies supported, beware! For example, the HTC Desire Z sold in Europe or Asia does not support 3G in the US, at all.

So you would like to get a local sim card for your trip to the USA?

3. In the US Prepay accounts with data are fairly limited and expensive

You are more likely to have a phone that supports AT&T’s 3G, as all iPhones do. But even with a compatible phone, prepay sim card accounts are quite expensive, and offer various restrictions on data connectivity or pricing:

  • UPDATED AT&T – Their GoPhone prepaid option finally now offers a sensibly priced option for unlimited data use. The new $50 plan, launched in June 2011 is good for unlimited talk, text and data. Beware that without this unlimited plan data is charged at a whopping $20 per Mb. (If you have an iPad see below for more on that later).
  • h2Owireless – a virtual network operating on AT&T, they are offering an all you can eat talk, text and data plan for $60
  • T-Mobile – I’m a big fan of T-Mobile, their “4G” network is fast, and their pricing is much cheaper than AT&T. (No longer the case). It really worked great on a business trip in Sept 2010 where I left my laptop tethered to phone all day long; the connection was rock solid and fast. (Sadly, a year later in Sept 2011 that was not the case, I just couldn’t get tethering to work at all). There is one big drawback with T-Mobile, your phone is less likely to be compatible with their flavour of 3G. Assuming you can get a compatible phone, T-Mobile now offer unlimited data on Pay As You Go. To use it you have to buy a $1.49 Web DayPass every day for 24 hours unlimited web access by clicking this link on your phone, which should pop up when you try accessing any website in your browser. If you are a more frequent visitor, or a heavier user their Prepaid plans are great value. Unlimited Text and Data can be had from $30 per month. As a third alternative T-Mobile also offer data-only prepaid plans, for $10 you can get 100Mb which lasts 7 days, or for $50 you can get 1Gb which lasts a month.  T-Mobile also support tethering, although you may have to pay an additional $15 for that (I believe it depends which phone you have). To get a T-Mobile SIM visit any T-Mobile store. The SIM costs $10, and includes $3 credit.
  • Simple Mobile – a “mobile virtual network operator” on the T-Mobile network. Just $60 for their sim only unlimited talk, text and data plan.

Anything else?

Do remember, to use a local sim you need to make sure your phone is unlocked.

Google Voice:

I really recommend this fantastic free service where you can claim a US number and make free calls from your PC. But the cool thing is you can divert this number for free to any US landline or mobile number, receive voicemail transcripts by email and, best of all, access the number online when you are outside the US and still receive calls, texts or voicemail. Pay as you go mobile numbers will eventually expire if not used, so it’s better to put the Google Voice number on your business cards. Please note, to register for a Google Voice number you will need to access the above link from an IP address inside the US. (Or you can use a VPN service to do this from outside the US).

What about the iPhone?

The iPhone 4, 3GS and 3G will work only with AT&T.

What about the iPad?

This is also compatible only with AT&T, but the good news is AT&T do a special iPad data-only prepaid plan. For $25 you can buy a block of 2Gb, which lasts for up to 30 days. If it runs out you can buy another block; cool. Not so cool is that to get a sim card you’ll have to go to an AT&T shop and pay $15. You’ll also most likely need a US credit card to activate it, although my UK issued Amex card worked fine with a made-up US address. If your card is rejected you can get around this by going to CVS or Walgreens and getting a prepaid VISA card to make the payment with. I thought the special iPad plan would be a great way to get a cheap data plan for a dongle, mifi or even to use with a phone but I believe the sim card will only work in an iPad. If you know otherwise, please let me know!


Truphone is a global mobile network operator which offers one sim card which works in the US, UK and Australia, and can have a local mobile number in each country. In the US data is charged at 20p per Mb, and it uses the T-Mobile network.

Although they are few and far between now, dual-mode phones are likely to become more common. The next iPhone is rumoured to support both CDMA and GSM based networks and this may make it easier to use Sprint or Verizon when in the US and a GSM network when outside the US. Dual-mode phones currently available include the Motorola Droid Pro XT610 and the BlackBerry Bold 9650.


  • Are there are phones that will work on both T-Mobile USA and AT&T, as well as access 3G world-wide? Yes, there’s a few smartphones that support 3G on 1700/1900/2100.
  • I really want to use T-Mobile 3G, where can I buy a compatible phone? You can buy compatible phones but they are harder to find outside of the US. It might be better to pick up an official branded T-Mobile USA phone on ebay or Craigslist. They will work for 3G outside the US too, assuming the phone is unlocked.
  • Will things change when AT&T and T-Mobile merge? In March 2011 AT&T announced they had reached agreement to acquire T-Mobile USA. Both businesses will continue to be run separately for the foreseeable future pending regulatory approval, and if this is granted it will take even more time for pricing and technical issues to be resolved. The latest (Sept 2011) is that AT&T have a long battle ahead of them to get regulatory approval for this merger, so it’s business as usual.

Who am I?

I’m Scott Allison, this is my blog. I started my first business selling mobile phones online in 1996, then co-founded award winning B2B telco abica, and now I’m working on new business, Teamly. I’ll be at SXSW in March, please say hello if you see me!

Groupon – no thanks

February 12, 2011

Like any good Scotsman I love a bargain, and I definitely enjoyed a shiny “oh-look” mentality when I first signed up. But 6 months in and I’ve unsubscribed. I was beginning to get fed up of the utterly irrelevant offers they were sending me, but the final straw was forgetting to redeem another voucher. I realised that my net position across all the Groupons I had bought left me either at break even, or possibly worse off.

I guess they can continue in this vein for quite a while, presumably there’s still plenty of noobs, but I’m off. Oh, and their superbowl ads were dire.

Here’s the last 20 deals I got sent by Groupon. There’s no pattern to them, they don’t even know if I’m male or female. It’s totally random.