Buying a Three Sim Card for Europe and UK: Europe Travel Sim Cards

By Phil Young, July 6 2018
Buying a Three Sim Card for Europe and UK: Europe Travel Sim Cards

Mobile telco Three (also known as 3) offers great value for prepaid roaming SIM plans which can be used throughout the UK as well as in Europe, with free data roaming on your smartphone or tablet.

I regularly travel to London, the UK and Europe and Three's pay-as-you-go SIM is a must-have item on my trips.

This guide will help you get up and running with a Three roaming SIM card in London. 

Where to buy your Three SIM card

You can buy a Three SIM from any Three store in the UK, on arrival at Heathrow Airport or online from Australian prepaid SIM supplier Simcorner. The SIMs are multi-size so they fit all phones.

Three's All-in-One 20 starter plan comes with 12GB of data per month, which should be enough for a few weeks, plus 3,000 minutes of talk time within the UK (or 300 minutes when roaming in Europe) and 3,000 texts sent around the world.

If you want buy the SIM card before you fly out from Australia, Simcorner charges $50 for this 12GB/month SIM plus $5 for delivery.

Another option is the vending machine neat the luggage carousels at Heathrow Airport Terminal 3 (the terminal used by for Qantas and Cathay Pacific flights, among others) which charges £30 ($52) for the 12GB card.

However, Three charges just £20 ($35) for the same SIM at any of its UK stores. The Three stores are accustomed to travellers buying a prepaid SIM, especially the London shops, and they’ll help you with setting up the SIM and account unless the store is very busy.

You can also pick up a Three SIM card without any plan – just the card itself – from any Sainsbury's supermarket for £1, and then buy a top-up voucher to set up your chosen monthly plan.

Hotspotting with a Three prepaid SIM

‘Tethering’ is when you use your smartphone to create either a WiFi hotspot or a wired connection to your laptop or tablet.

This is very handy for connecting a laptop to the Internet when there is no public WiFi available.

While Three officially doesn’t allow tethering, I’ve always had tethering work in the UK, although it only occasionally works when roaming in Europe. 

Roaming around Europe

When using a new Three SIM card in a roaming country you should have first used it for a ‘chargeable event’ in the UK – a quick call, SMS or online session will do. Although Three doesn’t always enforce this, if you are transiting from Heathrow to Europe it’s best to activate your Three SIM while at Heathrow Airport with a quick SMS back home so you can be sure that it will roam.

Enable any Roaming setting on your smartphone and also check that roaming is enabled in your online account at (look under the International Settings section).

Three lets you use 12GB of data per month in any of their 71 roaming countries, but limits your roaming to two months a year or checks that the majority of your usage has been in the UK over a period of four months.

Of course, if you’ll be using your Three SIM for just one trip this won’t be an issue.

While roaming you can make voice calls only back to the UK, with the cost of those calls coming out of your 300 minute monthly roaming allowance. Incoming calls are free.

If you want to make voice calls to countries other than UK, even local calls to the European country you’re currently in, you must have credit loaded on your SIM account. You can do that by getting and activating a top-up voucher.

(The alternative is to make Skype voice calls from your phone, provided there’s credit in your Skype account.) 

Roaming around the world

Three’s SIM plans also cover roaming to many countries outside the UK and Europe such as Brazil, Chile, Singapore, Hong Kong and Macau, Indonesia, Vietnam, even New Zealand and the USA.

However, you might find it preferable to buy a local pre-paid SIM card in those countries. It can be easier and cheaper to top up, and your local contacts may prefer to dial a local mobile number instead of one based in the UK.

Topping up your Three prepaid SIM

To top-up your Three SIM plan for voice calls in Europe or after your first month has ended, you can buy a top-up voucher from almost any UK convenience store or supermarket.

The voucher has a one-time-only code to add credit to your account. Call 444 and go through the prompts to top-up your account.

While you can also do an online top-up through your account on the website, credit cards issued outside the UK aren’t accepted for this, so I suggest buying to-up vouchers over the counter.

If you’re not in the UK and need to top-up your Three SIM, you can buy a ‘virtual’ top-up voucher from I’ve used this service and it works fine – they charge the same rates as Three plus an extra £1.50 service fee.

While the top-up adds credit to your account, you’ll want to convert that credit into what Three calls an ‘Add-on’ to set up a monthly plan.

Fail to do this – leave the top-up sitting in your account as straight credit – and Three will charge much higher rates for data and voice calls.

You can use your account’s credit to ‘buy’ an add-on directly from your smartphone in the UK, or via your online account if you’re overseas. 

Three has several add-on ‘All-in-One’ plans which last for 30 days and include 3,000 minutes of talk within the UK and 300 minutes when roaming, plus 3,000 texts to any number worldwide:

  • All-in-One 10: £10 for 1GB of data
  • All-in-One 15: £15 for 5GB of data
  • All-in-One 20: £20 for 12GB of data
  • All-in-One 25: £25 for 30GB of data
  • All-in-One 35: £35 for unlimited data

Using your Three SIM on your next UK visit

Your Three SIM account will remain active for six months without a top-up.

That means you can use the same SIM for multiple trips to the UK, as long as there’s no more than six months between each use of the SIM.

If you’ll be returning to the UK you can put enough value in your Three account just before you leave so that you can easily convert that value into a plan when you return to the UK, or even do it online before you fly in.

My advice is to register your SIM online at so that you can manage your account and top-up your phone using a ‘virtual' voucher if you’re away from the UK.

Phil Young

Having made the move from information management to photography, Phil combines his love of travel (London is his favourite destination) with the opportunity to shoot landscapes and wildlife in remote areas such as the Arctic, Africa and the Galapagos Islands.

Qantas - Qantas Frequent Flyer

05 Sep 2016

Total posts 14

I found Three fine for a one off trip to London. However, be aware that Three consider the roaming time to be the total duration from first roaming use outside the UK to when the next time you return to the UK, regardless of the actual time the sim card was active. I got caught out by this and had my roaming suspended which made the sim card useless outside the UK. Instead I now use the EE sim card which whilst less generous than Three does not have the same restrictions on roaming time.


16 Oct 2015

Total posts 10

But the Tories have already indicated that the UK will not stay in the EU framework that has made roaming so affordable. In other words, as of April 2019 the roaming benefits will quite probably be rather different.

03 Nov 2014

Total posts 90

It allows roaming in many countries outside of the EU - HK, USA, Australia, NZ etc - sure it will be fine when they get out as it's not available simply due to being in the EU.

Virgin Australia - Velocity Rewards

26 Jun 2011

Total posts 78

"When using a new Three SIM card in a roaming country you should have first used it for a ‘chargeable event’ in the UK".

That doesn't soundhelpful if you're arriving in Europe before the UK?

13 Sep 2016

Total posts 177

In which case this probably isn't the plan for you, you will need to look at a carrier in the EU which has roaming to the UK.


22 Oct 2012

Total posts 317

Three's website explains that their PAYG SIMs are primarily for UK residents who do some travel to these roaming countries. But Three does not always enforce their own T&Cs, and I hear stories of users being able to activate a 3 SIM in a roaming country, whilst others have problems doing this.

Etihad - Etihad Guest

06 Apr 2012

Total posts 123

Excellent review, Phil. BTW. Have also found the 'EUROPE & UK SIM CARD' offering that SimCorner sell also to be a good option. Costs about $40. The SimCorner web web site says it comes with 5Gb of data, but when I activated it in the Netherlands a couple of weeks ago I found it provided 10Gb. Tethering/Hotspotting also supported. Another unexpected surprise was that I found I was able to top-up the card with my Australian credit card (which I did not think would be possible). The sim card itself is actually provided by UK carrier 'EE'.

Virgin Australia - Velocity Rewards

13 Jan 2015

Total posts 584

I've used the 3 prepaid sims unlimited data plan for my last few trips to UK and europe...unlimited data (in UK at least) for $60 is cheap when you compare to the equivalent plan in aus...oh wait, we don't have unlimited

20 Sep 2017

Total posts 26

This is not just Three. All European providers have free roaming. Vodafone UK include Turkey in Europe. I doubt it will disappear with Brexit (not immediately anyway).

03 Dec 2016

Total posts 4

this prepaid sim is fantastic, the list of countries it works in is huge... a lot of european sims won't do data roaming in switzerland (but this one does), plus it works back home in australia too. you can sometimes get them cheper on

03 Dec 2016

Total posts 4

get them cheaper on ozbargain. i paid $25 delivered for mine.

26 Oct 2017

Total posts 6

Many thanks for this story Phil, and the various comments. You’ve just saved me a bunch of cash 👍

Virgin Australia - Velocity Rewards

17 Mar 2016

Total posts 43

I'm writing this now on my phone with a 3 Sim card while waiting in Bangkok. I bought the £20 card from their Hounslow store, close to the airport. 12gb was more than I needed during the 3 weeks I've been away. I even went to the USA in that time and the card served me well there too, saving me having to buy a separate card for the week I was there too. Across Europe I never had an issue, although often I was limited to 3G or even 2G but I think this was my phone frequencies and not because of the card.

United Airlines - Mileage Plus

12 Sep 2011

Total posts 329

Try for their mobile plan cheaper easier and worldwide including Israel and USA and Hong Kong Been using it for years! and you get to keep your number for years! just like my Tmobile USA US$3 per day with 200mb @4G daily then slows down Same US cel lnumber for years!

I went to UK recently and bought a 3 sim card for 75 pence in Aldi. I didn't want data because I was staying with friends, who had unlimited wifi, so I used my tablet for that. I chose 3 because their prices were the best and also my friends were on the same network. I put 5 GBP on and only used about 2 GBP in 3 weeks, with just phone calls and texts.

Qantas - Qantas Frequent Flyer

04 Jul 2018

Total posts 9

Great article. I have tried many prepaid SIMs in Europe over the last few years. Vodafone bought in Germany and bought in Portugal and one bought in UK. Lebara and Lyca bought and used in France and also Italy. I bought and used used T-mobile in USA last year, but Three from UK is still the best. After I went through all my SIMs in June, I found all the others had expired. My UK Morrison’s-bought Three prepaid had over six pounds unexpired credit to use in Germany in June this year. This was after two years idle. Amazing. Add-on packs for bonus calling or data expire, but base credit doesn’t. I would recommend using the SIM in your phone with roaming on, in Australia once a year to keep it live. I use Mobiletopup to buy vouchers in GBP with a non UK Visa card, you can use PayPal too, their voucher fee to do so is small. Although the Three UK website is fine, I setup the mobile app too, for the Apple store UK app you will need another UK registered Apple ID but then it’s easy to check balance etc anywhere in the world with WiFi on your phone.


22 Oct 2012

Total posts 317

That's encouraging news that you've had a Three SIM work after 2 years idle time. It seems that Three doesn't abide by their own T&Cs when it suits them.

I used to be able to use my Three SIM in Australia every few months to keep it alive, but that option ended about 2 years ago, for I was no longer able to connect to their network. I called Three, and their advice was that I can no longer use any cash credit in a Feel-at-Home country after the Add-on expires.

Qantas - Qantas Frequent Flyer

04 Jul 2018

Total posts 9

So Phil, that’s the case for Add-ons I think but the base credit, that isn’t converted to add on, will still remain. A bit like the Telstra prepaid credit that lasts 12 months. The older Three mobile prepaid I bought over four years ago from a Three store expired after a year being idle, but the newer one or two pound pack, bought May 2016 at Morrison’s, the base credit stayed. I just picked a pack with a long expiry also... The other issue is that there a max amount of roaming you can do in non-UK countries at the roaming rate, I’ve not hit that limit yet, but as far as I can tell you will just go into a higher cost rate, extracted from your base credit. My point here I guess is don’t activate add ons unless you are in UK or they are for a special deal for data in a country you are in, just mobiletopup base credit, oh and grab a Three multifit phone SIM card, not a data only one. It works in iPad, iPhone and in an unlocked Telstra 4G USB-powered wingle (good for the rental car, or in the acomodation or with a USB powerbank).

14 Oct 2018

Total posts 1

Great article. I've just been online chatting with three as I need to pick up a SIM at Heathrow, he assured me there is a dedicated Three kiosk in T3 (not the overpriced vending machine, nor sim local) - although I cannot reference to a kiosk anywhere... can anyone verify?

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