A reader writes in with this question about renting SIM cards in the US, traveling from Australia. The answer in the next section might also help others traveling from the US to a foreign country, as well as those who have phones without a SIM card.
My partner and I live in Australia and are just about to visit USA in 4 weeks time. We have what we call “SIM” cards in our smart phones (you may call them “air cards”, but I’m not sure if air cards are the same thing as SIM cards).
My question is, can we buy a prepaid “SIM” card (which is valid for say 4 weeks) from a telecommunications company in the USA which will give us internet and telephone coverage on our smartphones? I have a Samsung S2, and my partner has an I-Phone 4. I bought such a card in England and in Italy last year from local telecommunications companies (O2 in UK, TIM (Telecom Italy) in Italy), and they worked fine on my Samsung.
The short answer is yes. There are a few wireless companies in the US that will loan you a SIM card while you're here so you can use your smartphones for internet access and calls.
First, though, the best news is that your phones have SIM cards (and yes, we call them SIM cards here, but some people do use the phrase "air cards" to refer to the same thing, even though AirCard is a brand name for a specific mobile broadband card). Most cell phones around the globe (in over 220 countries) use the GSM (Global System for Mobile communication) technology, but in the US, major cell phone providers Verizon and Sprint more often have non-global ready (CDMA-only) cell phones. So renting a SIM card is actually more of an issue for US citizens who want to use their phones to make international calls when traveling. (An option if your phone doesn't have a SIM card: rent a smartphone or mobile hotspot (for your laptop). Unfortunately, that doesn't give you the benefit of using your own phone, complete with your installed apps and contacts, that a SIM card rental does.)
However, T-Mobile and AT&T networks support GSM phones compatible of global roaming. (I'm with T-Mobile and have the Galaxy S2, so that would work for you. However, you probably will want to go with AT&T, for the best compatibility with the iPhone 4 and 3G network speeds.)
PC Magazine recently did a nice overview of additional prepaid SIM options for visitors to the US. In addition to T-Mobile and AT&T, the article mentions smaller networks like Ultra Mobile and Straight Talk, which run on T-Mobile and AT&T networks. You'll need to pick the plan that makes the most sense for your usage while you're on vacation (or working vacation).
For example, for really short visits, PC Mag recommends Ready SIM's $25 7-day card, which includes unlimited talk, text, and 500MB of data. The 14-day version, with 1GB of data, is just $10 more. Ready SIM runs on the T-Mobile network.
AT&T's own plans start at $30 a month for 250 talk minutes ($10 for unlimited international calls to landlines), unlimited text messages, and a measly 50MB of data (not great if you're going to be using mobile data heavily, such as with frequent Google Maps lookups).
T-Mobile also starts at $30 a month, which includes 100 talk minutes ($10 for unlimited calls to landlines), unlimited text messages, and a decent 5GB of data.
See PC Mag's comparison chart for additional services and plans. Your best bet may be to contact T-Mobile and AT&T for help with your options.
Whichever service you decide to use, make sure you monitor your mobile data usage so you don't go overboard.
Update: Nice note back from Nick:
Hi Melanie, you replied to a query of mine (see below) a month ago - just to let you know we arrived in San Francisco two days ago, and purchased a SIM card from AT&T which works fine in my aussie Samsung S2, for both phone & data. So very happy, and thank you for your advice...