Best SIM Cards for Using Your Smartphone in the USA

If you’re travelling to the United States, having the right SIM card can save you a lot of money. We review the best value SIM cards for using your smartphone in the US.

Each year, almost 4 million Brits visit the USA. Whether you’re travelling to New York to do a bit of shopping, touring California to enjoy the beautiful scenery or visiting Florida to enjoy the theme parks with your family, you’ll probably want to use your mobile phone whilst you’re there.

Having a smartphone in America can make it a lot easier to stay in touch with friends and family who are back in the UK. It can also be useful for navigating around (e.g. finding nearby restaurants or attractions with Google Maps).

The good news is it’s now really easy to take a UK smartphone and to use it in the US. You can either roam on your UK SIM card or you can buy a US SIM card upon your arrival in the States. In this article, we’ll review and compare the best SIM cards for using your smartphone in the US. We’ll also compare the cost of using different SIM cards and will discuss network compatibility with your UK handset.

Using a UK Smartphone on US Mobile Networks

Almost all UK smartphones sold in the past decade will work in the US without any problems. Typically, you can get 3G coverage from AT&T and both 2G & 3G coverage from T-Mobile USA. On a limited selection of newer handsets, it may also be possible to get some 4G coverage from the two mobile networks.

If you’re using a fairly old handset or if your smartphone was purchased outside the UK, you should double-check to make sure your handset will work. Your phone will need to support at least one of the following frequencies for it to work in the US:

• For AT&T, your handset will need to support one of the following:
  • For 2G: AT&T switched off their 2G coverage in January 2017.
  • For 3G: WCDMA/HSPA 850 or WCDMA/HSPA 1900
  • For 4G: LTE bands 2, 4, 5, 12 or 17
• For T-Mobile, your handset will need to support one of the following:
  • For 2G: GSM 1900
  • For 3G: WCDMA/HSPA 1900 or WCDMA/HSPA 1700/2100 (AWS)
  • For 4G: LTE bands 2, 4, 12, 66 or 71

You should check your manufacturer’s spec sheet to see a list of frequencies supported by your handset.

It isn’t normally possible to use a UK smartphone on Sprint or Verizon Wireless. This is because Sprint and Verizon use a different technology for their mobile networks (CDMA/EVDO) which is incompatible with most UK smartphones.

The Two Ways Of Using Your Smartphone in the US

There are two ways to use your smartphone in the US: you can either roam on a UK-based SIM card (setting it up before you go) or you can buy a new US-based SIM card upon your arrival in the States.

• Roaming on a UK-based SIM card. Through international roaming, you can continue to use a UK-based SIM card when travelling in the US. You’ll continue having a UK-based phone number and will be charged for usage through your UK network. You’ll normally be able to access coverage from both AT&T and T-Mobile USA. This is our recommended option for the majority of users. With a Pay As You Go SIM card from Three UK, you can use your smartphone in the US from just £10 for up to one month. This comes with inclusive data and inclusive calls back to the UK (including to other UK-based mobile numbers travelling abroad with you).
• Buying a new US-based SIM card on arrival. If you’d like a local phone number in the US, you can buy a US SIM card upon your arrival in the States. This can either be from AT&T or T-Mobile USA. You should expect to pay at least $30 plus tax (about £21.45 plus tax of around 10%). This will give you an allowance of US minutes and also an allowance of data to use on your phone (additional charges will apply for calling back to the UK). You’ll need to buy your SIM card in person when you arrive in the US (typically, you’ll also need either a US-based credit card or cash to pay for your top-up). Typically, it will only be worth getting a local US SIM card if you regularly travel there for extended amounts of time.

Roaming On Your UK SIM Card

The simplest and easiest way to use your smartphone in the US is via international roaming on your existing UK SIM card. The prices for using your phone in the US can vary depending on your home UK mobile network:

Network	Making a Phone Call	Receiving a Phone Call	Sending a Text	Accessing the Internet
BT Mobile	£1.40/minute	£1.25/minute	40p/text	£5/MB
EE	£1.20/minute	£1.00/minute	60p/text	£4/day for 40MB
giffgaff	£1.00/minute	£1.00/minute	30p/text	20p per MB
O2	£2.00/minute	£2.00/minute	50p/text	£7.20 per MB
Orange	£1.44/minute	£1.44/minute	60p/text	£3/day for 20MB
Plusnet Mobile	£2.50/minute	£1.00/minute	50p/text	£8/MB
Sky Mobile	96p/minute	96p/minute	42p/text	£5/day to use UK allowance
Tesco Mobile	£1.29/minute	89p/minute	40p/text	£5/MB
T-Mobile UK	£1.44/minute	£1.44/minute	60p/text	£4/day for 20MB
Three	Included	Included	Included	Included
Virgin Mobile	£1.80/minute	£1.20/minute	36p/text	£20/week for 50MB
Vodafone	£6/day to use your UK allowance of minutes, texts & internet

Comparison of roaming charges when using your UK-based SIM card in the US. The costs shown are for calling the UK and sending a text message to the UK. It’s always free to receive a text message wherever you are in the world.

If you’re roaming on a UK-based SIM card, you can normally benefit from coverage on both AT&T and T-Mobile USA (your smartphone will automatically choose the network offering the strongest coverage).

The Best Network For Roaming in the US

Three is by far the cheapest mobile network for roaming in the US. When travelling to the United States of America, customers on Three can use their normal UK allowances at no extra charge. The offer is open to customers on both Pay Monthly (Advanced plans only) and Pay As You Go. For more information, please read our full review of the Feel At Home offer.

If you’re not currently a customer of Three, you can benefit from the offer by ordering a Three Pay As You Go SIM card. For instance, a £10 top-up will give you 3000 minutes, 3000 texts and 1GB of internet (up to 30 days usage in the US). You can upgrade this to 5GB of data for a £15 top-up or 12GB of data for a £20 top-up:

Network	Minutes	Texts	Internet	Monthly Cost
	Unlimited to UK	Unlimited to UK	2GB in UK & US	£10.00
	Unlimited to UK	Unlimited to UK	5GB in UK & US	£15.00
	Unlimited to UK	Unlimited to UK	12GB in UK & US	£20.00

With an “All in One” Pay As You Go bundle, the inclusive minutes, texts and internet can be used abroad in the United States at no additional charge.

Your inclusive minutes and texts can only be used for calling a UK-based phone number. This includes any friends or family members who are also abroad with you at the same time and using a UK-based phone number (your friends or family members could also be using another SIM card from Three). Phone calls to a US-based phone number will cost you £1.40/minute extra.

As an alternative to the Feel At Home offer, customers on an EE Max tariff will also get roaming in the US included with their plan.

Buying A US SIM Card On Arrival

If you regularly travel to the United States for an extended amount of time, you might be better off buying a local SIM card from one of two US networks. If you’re using your unlocked UK smartphone, you have the option of a SIM card from either AT&T or T-Mobile USA. Unfortunately, the Sprint and Verizon networks will not work on most UK-purchased smartphones.

You can buy a US SIM card upon your arrival in the States. Unfortunately, it’s not possible to buy one online as the US mobile networks will not only ship their SIM cards to the UK. You’ll be able to buy a SIM card in retailers like 7-Eleven, CVS, Target, Walgreens and Walmart. Alternatively, you can get a SIM card from AT&T or T-Mobile retail stores.

AT&T

AT&T is the biggest mobile network in the US. They’ve been established for a longer amount of time than T-Mobile USA, which gives them better nationwide coverage. At present, AT&T claims to offer 99% population coverage on 3G and 4G (their 2G service closed down in January 2017).

On AT&T, you can get a prepaid plan from $35/month plus tax. AT&T’s prepaid plans were historically known as “GoPhone” and as such, may still be referred to by this name in some places.

For a typical smartphone user visiting the US, we’d recommend the $45 GoPhone plan (approximately £32/month plus tax). This will give you 6GB of high-speed 4G data along with unlimited calls & unlimited texts within the US. Phone calls back to the UK will cost you 49¢/minute (35p/minute) plus tax, or you can buy the $5/month International Long Distance Package which gives you 250 minutes for calling a UK landline (approximately £3.58/month plus tax).

The following table shows Pay As You Go tariffs available from AT&T:

Network	Minutes	Texts	Internet	Monthly Cost (USD)	Approx Cost (GBP)
	Unlimited to US	Unlimited to US	1GB	$35.00 plus taxes	£25.01 plus taxes
	Unlimited to US	Unlimited to US	6GB	$45.00 plus taxes	£32.15 plus taxes
	Unlimited to US	Unlimited to US	Unlimited*	$65.00 plus taxes	£46.44 plus taxes

* On the $65/month AT&T prepaid plan with unlimited data, you’ll get full download speeds on the first 22GB of data usage. Thereafter, download speeds will be capped at 3Mbps.

You can get an AT&T prepaid SIM card from your nearest AT&T store. Alternatively, it will cost you $9.99 plus tax at most other retailers (approximately £7 plus tax).

The exact price you pay will depend on local tax rates (see a list of wireless tax rates for each US state). Before getting an AT&T SIM card, it’s worth checking the coverage at places where you’ll regularly visit (see AT&T’s online coverage map).

If you’re staying in the US for an extended amount of time, you may be able to get a $5/month discount by enrolling in AT&T’s AutoPay programme. We wouldn’t recommend this if you’re a short-term visitor as it means your AT&T SIM card will be topped up automatically every month.

Finally, it’s worth being aware that your AT&T prepaid SIM card will be deactivated automatically if you don’t top it up again within 60 days of your previous bundle expiring. For this reason, it will only be possible to re-use the SIM card on a subsequent trip if you plan to visit the US again within a 60-day period.

T-Mobile

In the US, T-Mobile is the third-largest mobile network when measured in terms of number of subscribers. It is a separate and independent network from T-Mobile UK, and the two should not be confused with each other.

On T-Mobile, there are two types of prepaid package. For short one-off trips, you can choose the 21-day International Tourist Plan. Meanwhile, regular visitors and customers who want to stay for more than 21 days can choose a regular prepaid package like Simply Prepaid or T-Mobile One.

For short-term visitors, we’d currently recommend the 21-day International Tourist SIM card. This comes with 1,000 US minutes, unlimited texts and 2GB of 4G data (beyond that, you’ll still be able to use the SIM card but speeds will be restricted to 150kbps or 0.15Mbps). The International Tourist Plan costs $30 plus tax (£21.45 plus tax). It cannot be renewed at the end of the 21-day period.

If you choose a regular prepaid package, it’s possible to get a larger allowance of data. The following table shows available options from T-Mobile USA (prices and allowances are shown on a per-month basis):

Network	Minutes	Texts	Internet	Monthly Cost (USD)	Approx Cost (GBP)
	Unlimited to US	Unlimited to US	4GB	$45.00 plus taxes	£32.17 plus taxes
	Unlimited to US	Unlimited to US	6GB	$55.00 plus taxes	£39.32 plus taxes
	Unlimited to US	Unlimited to US	Unlimited*	$75.00 plus taxes	£53.62 plus taxes

You can get a T-Mobile USA SIM card for $20 plus tax at any T-Mobile retail store.

The exact price you’ll pay for the SIM card and bundle will depend on the local tax rates in the state where you’re staying (see a list of wireless tax rates for each US state). Before getting a T-Mobile USA SIM card, it’s worth checking the coverage for the places where you’re staying.

If you choose the International Tourist Plan, your SIM card will expire after 21 days. Meanwhile, with other prepaid plans, you’ll be able to renew the bundle to continue using it. However, your SIM card will expire if you don’t top it up for a period of 90 days. For this reason, you’ll only be able to re-use your SIM card on subsequent trips if you expect to visit the US at least once every 3 months.

Our Recommended Deal

For the majority of visitors to the US, we’d recommend roaming on a UK-based SIM card. Three is by far the best UK mobile network from which to get a Pay As You Go SIM card. The SIM card is free and a top-up from £10 will get you up to 30 days usage over in the USA.

The following table gives a quick summary of the two options we’ve discussed in this article:

Roaming on your UK SIM card	Buying a new US SIM card on arrival
Best option for the majority of users.	Best option for frequent travellers to the US.
You’ll have a UK-based number (beginning with +44).	You’ll have a US-based number (beginning with +1).
We recommend the Pay As You Go SIM card from Three. There is no charge for this SIM card.	SIM cards are available from AT&T and T-Mobile USA. The SIM card is free or up to $20 (£16) plus tax.
Starts from £10 (including tax) for 30 days usage.	Starts from $35 (£25) plus tax for 30 days usage.
Coverage from both AT&T and T-Mobile USA.	Coverage from one network only.
Inclusive calls to UK-based phone numbers. Calls to a US phone number are £1.40/minute.	Inclusive calls to US-based phone numbers. Calls to the UK start from 49¢/minute (40p/minute) plus tax.
You can continue to use your SIM card in the UK after the end of your trip.	Your US SIM card will expire after 90 days unless you top it up again during this time (T-Mobile International Tourist SIM will expire after 21 days).

On Three, you can choose from several Pay As You Go bundles with which you’re able to use their Feel At Home offer:

Network	Minutes	Texts	Internet	Monthly Cost
	Unlimited to UK	Unlimited to UK	2GB in UK & US	£10.00
	Unlimited to UK	Unlimited to UK	5GB in UK & US	£15.00
	Unlimited to UK	Unlimited to UK	12GB in UK & US	£20.00

You’ll get the SIM card sent to your UK address so there’s one less thing to worry about when you arrive in the States. The SIM card will also work on both the AT&T and T-Mobile US networks. You’ll get a UK-based phone number and you’ll be able to use the inclusive minutes and texts to contact other UK-based numbers (this includes your friends and family who are also abroad with a UK-based number).

Customers of any UK mobile network can sign up for a SIM card from Three (all you need to do is to make sure your handset is unlocked). You can choose your All-in-One bundle when ordering your SIM card (for most people, we’d recommend the £15 bundle).

• US Roaming Price: £15/month for 3000 minutes, 3000 texts and 5GB of data
• Overages: 1p/MB once you’ve used 5GB (or choose the £20 bundle for a 12GB allowance)
• £15 top-up buys: Up to 30 days of smartphone usage in the US

Order Three Pay As You Go SIM Card →

We would only recommend buying a local SIM card upon your arrival in the States if you’re a frequent traveller requiring a US-based phone number. Of the two possible networks, AT&T has slightly lower prices so is our recommended network for anyone choosing a US-based SIM card.

Other Top Tips For Travelling To The US

When travelling to the US, it’s also worth bearing the following things in mind:

1. You’ll need an ESTA to fly to the US (it costs $14 or approximately £10 per person). If you’re travelling to the US by air or by sea (even if you’re only transiting through the US to another country), you’ll need to complete an online ESTA form (from the US Electronic System for Travel Authorisation). It costs $14 per person and lasts for two years (this is approximately £10 per person). There’s more information about this on GOV.UK and Money Saving Expert. You should always apply for your ESTA on the official website run by the US Department of Homeland Security.
2. Make sure your electronic devices have power before boarding. As of July 2014, there are extra security measures for travellers to the US. All electronic devices being carried in your hand luggage should have sufficient amounts of power for you to be able to turn them on. This includes your smartphone, tablet, laptop and e-book reader. You could be asked to switch on the device and to demonstrate its function when passing through airport security. As there are only limited charging points available at the airport, it’s probably a good idea to invest in a portable charger (prices start from around £12).
3. Make sure you have the relevant adapters for charging your electronics. You’ll need a UK-to-US plug adapter for charging your electronic devices (besides your mobile phone, consider whether you might need additional adapters for your laptop, hairdryer, shaver, etc).
4. Use TSA approved locks for securing your baggage. If you’re using a lock to secure your baggage, it must be TSA approved (see Amazon.co.uk for a list of TSA approved baggage locks). If you use a non-TSA approved lock, security teams at the airport may take a bolt cutter to your lock.