Buying a Prepaid UK Sim card at London Heathrow Airport and in London

Disclosure: This post may contain affiliate links that earn me a small commission, at no additional cost to you.

Buying a Prepaid UK sim card can help you save on roaming cost within the UK and depending on the sim card, possibly within the EU. Whether you’re staying in the UK or passing through Heathrow on your way to Europe this guide will help you pick up a sim card at the airport.

The UK has dozens of prepaid sim cards for tourists available, that unlock monthly data, calling and texting plans based on the amount you top-up. 

Brexit warning: Due to Brexit, networks have been changing how they handle EU roaming charges. Please make sure you double-check with your network before using the sim card abroad.

Some UK networks which used to have a fair usage policy for EU roaming have kept this in place, although the restrictions have tightened.

But, sadly most networks (including Three, EE, Vodafone and O2), are now charging daily fees for using your UK sim card abroad. I have covered the announced changes so far in this post but as roaming can get stupidly expensive please make sure to double-check the information I’m sharing with the phone network before travelling to Europe.

The Sky Garden in London, UK by Alison Fay

How to use a UK Prepaid Sim Card

Before travelling, make sure your phone is able to use UK Sim cards. You’ll need to make sure your phone is unlocked or contact your phone network to ask for an unlock code. Depending on the phone and where you live, there may also be a store or online website that can help.

The UK’s phone networks use LTE, with support for 2G, 3G, and 4G speeds. From 2020 onwards, within London, you can get 5G data from the UK’s main phone networks.

The quality coverage of 5G and 4G you get will vary depending on where you’re going but within London and other UK cities, you can expect to have 4G. 5G.

If you’re staying in or visiting London, and have a 5G phone make sure to buy a 5G UK Sim Card to make use of the latest London phone network technology.

Below’s a table of the band frequencies that the UK mobile phone network uses, make sure your phone supports these before you buy a sim card.


Band type

EE Band 3 (1800MHz) and Band 7 (2600MHz) 
ThreeBand 3 (1800MHz) and Band 20 (800MHz)
O2Band 20 (800MHz) 
VodafoneBand 20 (800MHz) and Band 7 (2600MHz)

European networks mostly use the same technology but I recommend checking this Wikipedia list of mobile networks to confirm what network types are available in the EU countries you’ll be visiting.

If you have a dual-sim phone, make sure you configure your sim card settings to use the UK sim card. Ensure roaming is disabled on your home countries sim, otherwise, you may end up with a huge bill.

Buying a sim card from Sim Local at Heathrow Airport

Sim Local stores are located in London Heathrow Terminal 2, 3 and 5 plus the underground in Terminal 2. They’re all open from 6 am to 10 pm* so if you’re arriving within these times you can easily grab a sim card. If you need assistance installing the sim card or figuring out which plan you need, then I recommend going to one of these stores. But If you’d prefer to do it yourself, then go to WHSmiths or a vending machine.

*These times may change due to covid, but don’t panic if the store’s closed. I also cover how to purchase sim cards at a UK supermarket, which are open during normal hours.

Buying a sim card from WHSmiths at Heathrow Airport

WHSmith store inside London Heathrow Airport
(Ceri Breeze) /

WHSmiths has a range of UK Prepaid sim cards available. These are also sold by Sim Local but this way, you get to do it yourself without having to deal with someone trying to upsell things you probably won’t want.

So if you don’t need assistance with buying and installing the sim card, I recommend going here. Just make sure you have a paper clip or a sim card slot opener on you or you’ll have to pop to Sim Local or the tourist information for help installing it.

If you do have an issue with the London sim card you purchased from WHSmiths, you can pop into the Sim Local store and they’ll be able to help fix it. I recommend checking the prepaid sim card works before you leave the airport, otherwise, you’d have to return if there’s an issue.

WHSmith stores can be found in the arrivals for Terminal 2, 4 and 5. They’re also in the Landside arrivals area for terminal 3, and the landside main in terminal 4. They’re open from 6:30 am until 10 pm.

London Prepaid Tourist Sim card vending machines

Sim Local has a few vending machines that contain sim cards, dotted around each of the terminals — normally next to the drink and food vending machines. So if your flight is arriving after 10 pm or if you want to DIY it, you can buy a prepaid UK sim card from the vending machine and if there’s an issue, you can still go to the SIM Local store to have it resolved (if arriving before 10 pm). But once again, make sure you have the sim card opener/paper clip.

The vending machines have sim cards for EE, Three, Lyrca and Vodafone. They can sometimes have better deals than the store but if you’re on a budget it is worth checking each of the options mentioned in this travel guide before buying a sim.

Buying a UK sim card from WeKnow

WeKnow is the tourist information for London, and have prepaid sim cards for EE and Three available.  They’re located in the arrival areas for Terminal 2, 3, 4 and 5. They’re open from 5:30 am to midnight in Terminals 3 and 5, and from 6 am to midnight in Terminals 2 and 4. Their sim cards, are more expensive than those you’ll get outside the airport but if you need a sim card straight away they’re not the worst option – especially if you need help setting it up.

Here’s some examples of the plans available:




EE (5G available)40GB Data / 80GB Data / 120GB data for 30 days, unlimited UK calls+texts.
Roaming data allowance includes the EU/EEA
Three (5G Available)12GB / 30GB / 50GB / Unlimited data, for 30 days. All plans have unlimited UK calls+ texts£25-£50
Lyca Mobile1GB data, 100 UK Texts, 500 UK minutes, 500 International minutes£25
Lyca Mobile5GB Data, Unlimited UK calls + texts,  with 1000 call minutes to India£30
Three3000 minutes, 3000 texts, Unlimited data in the UK, up to 12GB data within the EU.£50

If you want to, you can reserve and pay in advance for the sim card with WeKnow online,  you’ll be asked to select your pickup location and time when ordering so make sure to double-check your flight information to make sure you have the correct terminal.

Buying a London sim card in the departure area

If you’re staying within the departure area to meet a connecting flight, you can get an EE sim card from Dixons Travel (after security) or reserve it online. It’ll give you 150minutes of call time and 500MB of data within 34 countries for £10; which is a rip-off and sucks but that’s sadly all they have available after security. You can also try WHSmith’s, as they normally have some sim cards available on the departure side.

EE Pay as you go sim card packaging that reads: 150 mins, to call within the UK and to 34 countries plus 500MB data.

Dixons Travel is located in Terminal 1, 2, 3 and 5. They’re open from 5:30 am to 10 pm in Terminal 1, 3 and 5 and from 6 am to 10 pm in terminal 2.

WHSmith is located in Terminal 2, 3, 4 and 5 after security and in Terminal 3, 4 and 5 before security. Most of the stores are open from 5:30 am to 10 pm but some are open earlier.

What to do if your sim card doesn’t work

I really do recommend making sure your sim card is working before leaving the airport, to avoid the hassle and cost of having to return to the airport.

If you’ve installed your sim card, and it has an error such as “no sim detected”, try restarting your phone. If this doesn’t work, try removing the sim card, and re-inserting it. If that still didn’t fix it then you’ll need to go to the Sim Local store.

If you have already left the airport, and cannot go back then your best bet is to contact the network provider and Sim Local. Sim Local used to have a refund request page but this has been taken down, so you’ll need to contact them via their contact page or you can email or ring them (the information is on the contact page). To contact your network provider without a mobile phone is quite a hassle, you might need to go into one of their stores or ask wherever you’re staying if they have a phone you could use.

Buying prepaid sims outside of the airport in London

If you can manage without a sim card until you’re away from the airport, then I highly recommend doing so – especially if you’re on a budget. The sim cards sold in Heathrow Airport are a lot more expensive than those sold in stores away from the airport.

Sim cards by the checkout in Asda
Prepaid UK Sim cards by the checkout in Asda Supermarket in England

Sim cards are available from most convenience stores, such as Tesco Express, Sainsbury’s, and Co-op. You’ll also find them in their supermarkets, as well as Asda supermarket. They’re normally located near the checkout. You normally have to top up at least £10 when buying the sim card.

Supermarkets have much better sim card deals than the airport. Here are some examples of offers available from UK networks, as of June 2021 using supermarket sim cards:

A £10 top up with GiffGaff will give you access to 10GB of data and unlimited UK texts + minutes for 30 days. With EE, a £10 top-up gets you 100 UK minutes, unlimited texts and 4GB of data for 30 days.

Some supermarkets such as Asda and Tesco, have their own-brand sim cards. Asda mobile uses Vodafone’s network and gives you unlimited minutes, texts and 10GB of Data – you’ll also get access to 5G if in a 5G coverage area. Whereas Tesco, uses the O2 network, and a £10 top up with Tesco will give you a 4G sim card that has 5000 minutes, 5000 texts and 10GB of data.

EE Sim Card, £1 for 2GB data and 100 minutes + unlimited texts
An EE Sim Card from August 2019, sold in Asda offering 2GB data and 100 minutes + unlimited texts for £10.

You can also find London sim cards in shops like Argos, such as £15 for 15GB of data, unlimited minutes + texts with Vodafone. If you’re going to be using a lot of data in the UK, then VOXI offers 45GB of data for £20. This sim card is available from Argos.

Screenshot of Vodafone, O2 and VOIX Sim cards on the Arogs website

Ordering a UK Sim Card Online

You can also order UK sim cards in advance online from Amazon, and have them delivered to an Amazon Locker. Amazon lockers are found in a lot of stores, around London so you can easily arrange to have one delivered to the locker.

Such as this 36GB Simcard with unlimited calls and texts from Three, including up to 12GB of data roaming within 49 countries in Europe, or, this preloaded EE Sim Card with 6GB Data that lasts for 90 days. There’s also a Vodafone sim card with 15GB of data that lasts for 90 days + international calling.

You can also order a sim card online directly from the UK mobile network. These sim cards either require you to pay online when ordering for a pay-as-you-go plan, or they send you a free sim card which you load credit onto when you receive it.

I personally recommend ordering a free GiffGaff sim card. They’re a cheap network with good deals, and use the O2 network which has really good 4G and 3G coverage across the UK plus 5G coverage in London (and other cities). Their deals include 8GB of data, unlimited minutes and texts for £10, or get unlimited data (with a fair usage policy) for £25.

Screenshot of Giffgaff's Goody Bag offers as of October 2019.

Other companies you can order sim cards from include:

Vodafone, from £10 for 5GB data. 

Asda, from £10 for 10GB of data

EE, from £10 for 5GB of data

Three, from £10 for 6GB of data 

O2, from £10 for 7GB Data. 

The above plans are correct as of 25/08/2021. Remember to compare the different UK network’s plans before ordering as they regularly offer deals throughout the year, such as double data.

Need international calling? Lycamobile and Giffgaff offer cheap international calling and their sim cards can be ordered online.

If you’re planning on using a mobile WiFi device, then why not check out these plans and devices that can be ordered online.


Mobile Wifi Device / Mobile Wifi Plan

SkyroamMobile WiFi Hotspot & Power Bank, works in 130+ countries including the UK and Europe.
SkyroamSkyroam Pre-Paid Card: 5 Global WiFi Day passes 
GlocalMeGlocalMe G3 4G Mobile WiFi Hotspot, with 1.1GB Global data
ThreeMobile Broadband 24 GB Data SIM
EEEE PAYG SIM Card Preloaded with 24 GB of 4GEE Data
GMYLEPrepaid Travel Sim with 200 MB Global Data
HuaweiHuawei E5573Cs-322, 4G Travel Hotspot this is the I use!
TP-LinkTP-Link M7350 4G LTE MiFi Device (No Sim Card included)

Buying UK Simcards in other countries

Depending on where you’re coming from, It is possible to pick up a UK sim card or an international tourist sim card that works in the UK, and sometimes multiple countries before you arrive. This is a great way of guaranteeing you’ll have a working sim card soon as you land, and might save you time.

If you’re flying from Bangkok, you can pick up a 4G Sim Card with unlimited data, that lasts for 15 days from Bangkok Airport.

If you’re flying from Hong Kong, you can order a UK Three Sim Card to collect from the arrivals hall in Hong Kong airport. This travel-friendly sim card gives you 5GB of internet data to use in 42 countries, including the EU, the UK, Hong Kong, and Macau. These sim cards last for 30 days.

Coming from Singapore? You can order this 4G Sim Card, that works throughout Europe with 2 different plans available (2.5GB data for 7 days or 5GB data for 20 days). This sim card will be shipped to you so you make sure to order in advance to ensure there’s time for you to receive the sim card.

If you’re flying from Ha Noi or Ho Chi Minh City, there is a 4G Sim Card with either 5GB data or 12GB data that lasts for 30 days. This sim card will be shipped, so make sure to order well in advance to get it in time for your flight.

If you’re coming from the USA, you can order European Sim Cards off Amazon that covers the UK and EU. Such as this Orange Sim Card that has 20GB of data, 120 minutes and 1000 texts, or a Three sim card that gives you 12GB for use in the UK and Europe for up to 1 year.

Other sim cards are available to pre-purchase in the USA.

If you found this guide to buying a UK prepaid sim card at Heathrow Airport helpful, please share it with your friends.

If you’re looking for cheap flights to Europe or the UK, check out my travel guide on buying cheap flights.

Still, need accommodation? I have a guide for finding cheap hotels & hostels as well.

If you’re staying in London and looking for some day trips, why not visit the beautiful Georgian city of Bath? or, make the day trip into a weekend by combining it with a visit to the beautiful county of Somerset?

Pin image for How to buy sim cards in London & Heathrow airport

5 thoughts on “Buying a Prepaid UK Sim card at London Heathrow Airport and in London”

  1. If I purchase a sim in the UK, can I make free calls to the USA or is it only free in the UK?
    Do the people I call get charged for international calls?
    Do I get charged if they call me?
    Also, are texts to and from the USA free?


  2. I had Amazon ship the Three 36GB data sim card you recommended to my hostel, arrived the day before I arrived. Cost me 35bucks which is so much cheaper than what AT&T wanted to charge me

  3. I ordered a giff gaff sim card free on line they posted it airmail to my New Zealand address all I have to do is load it into my phone on arrival select the goody bag and active the card using their app. Couldn’t be easier.
    Allow plenty of time for the mail, in these covid days it took 7 weeks to arrive

Leave a comment