Your options for getting online
As elsewhere, you can roam with your usual provider, buy a British SIM card or install a data eSIM. Our guide to eSIM, local SIM or roaming sets out the pros and cons of each.
Roaming: check before you travel
Since the UK left the EU, the European ‘Roam like at home’ rule no longer applies there. Each provider sets its own terms: some still include the UK in their plans, others charge extra for roaming or offer a paid add-on. Read your provider’s terms before you leave to avoid an unpleasant surprise on your bill.
A British SIM card
A local SIM gives you a UK number, which is practical for a long stay, a work placement or if people in the UK need to call you. You can buy one in a shop or online, and it replaces your usual SIM if your phone does not support dual SIM.
A data eSIM
The Alizeoo eSIM provides mobile data with no phone number and no standard calls; apps such as WhatsApp and FaceTime work over the internet. You install it before you go and your usual SIM stays in place for calls and texts. It is useful if your provider does not cover the UK on good terms. Your phone must support eSIM and be unlocked: check with our compatibility guide.
Networks and coverage
The main UK mobile operators are EE, O2, Vodafone and Three. The country has both 4G and 5G. Alizeoo plans for the UK run on partner operators, currently EE, O2 and Vodafone; the exact networks for each plan are listed on its page, as they can change. 5G is only used when the plan, the partner operator and your phone all support it.
Coverage is good in towns and cities and along major routes, with a few exceptions worth knowing:
- on the London Underground, mobile coverage depends on the line and the station;
- in the Scottish Highlands, parts of Wales and other rural areas, the signal can be weak or absent;
- on some minor country roads and in remote valleys.
Before a day out beyond the cities, download offline maps. If the eSIM will not connect where there is network coverage, follow our guide my eSIM has no signal.
Public Wi-Fi: good habits
Free Wi-Fi is easy to find in cafés, pubs, hotels, railway stations and many public places. It helps in a pinch, but it is often open:
- avoid entering card details or passwords on it;
- be wary of networks whose name does not clearly match the venue;
- keep your mobile data for payments and signing in to your accounts.
Useful apps
- In London, TfL Go or Citymapper for real-time Tube and bus times.
- Trainline or the National Rail app for trains between cities, with timetables and delays.
- Messaging and internet calling apps such as WhatsApp or FaceTime, since the eSIM does not come with a phone number.
Installing and activating your eSIM
You install the eSIM at home over Wi-Fi, and it takes a few minutes. The menus are covered step by step in our iPhone and Android guides.
- Choose a UK plan: the QR code and installation link arrive by email and in your account.
- Before you leave, on Wi-Fi: scan the QR code or tap ‘Install in one tap’, then name the line Alizeoo.
- When you arrive: select Alizeoo for mobile data and turn on data roaming for that line.
- Turn off data and roaming on your usual SIM: this matters all the more in the UK, where your provider may charge for roaming.
The plan’s validity usually starts the first time you connect in the UK; the plan page gives the details. To stay reachable on your usual number, see our dual SIM guide.
Planning a Europe plan for several countries? The UK is not always included in regional plans: check that it appears in the list of countries on the plan page before you buy.
How much data will you need?
Messaging, maps and transport apps use little data. Video, video calls and sharing photos and clips use more. If you want to connect a laptop, check that the plan allows tethering: this is shown on the plan page. For an estimate based on your usage and the length of your stay, use the estimator on our UK eSIM page.
Before you go
- Ask your provider about its roaming terms for the UK.
- Make sure your phone supports eSIM and is unlocked.
- Do not delete the eSIM once installed: it usually cannot be reinstalled with the same QR code.
- Download offline maps for the Highlands and rural areas.
- Travelling on to other countries? Plan your multi-country trip.
To choose a duration and data allowance, see the plans for the UK. Prices include tax and are shown in US dollars.