How to use eSims to save on mobile roaming abroad
Using data while travelling and avoiding an extortionate bill when you get home is a common concern for travellers. While trips to the EU are easier to manage with networks that offer free EU roaming allowances, venturing further abroad can still incur hefty charges.
Fortunately, the growing availability of eSims provides a solution to staying connected. Using an eSim can help you cut down on traditional roaming fees, provide cheaper access to local or regional data deals, and allow you to switch between networks just by using your phone’s settings.
Most travel eSims don't include calls and texts – the idea is that the eSim gives you data, which you use for apps such as maps, but also to make calls and send texts via internet-based apps rather than through traditional calling. We compare eSims to other roaming add-ons below to see how much they could save.
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How do eSims work for mobile roaming abroad?
A Sim tells your phone which mobile network it is connected to, and what your phone number is. Traditionally, a Sim has been a physical card you insert into your phone. An eSim exists purely as a chip and software inside your phone, so it's quicker to change.
eSims open up possibilities when travelling, as you can switch to a local data plan without needing to physically swap different Sim cards in and out of your phone.
All you need to do is purchase an eSim for the country you are travelling to, then install it on your phone using a QR code or download code. Finally, check the settings in your phone and switch to using the eSim for data.
For more on phones and networks that can use eSims, how to install one, and other benefits, read our guide to mobile phone eSims.
When should I use an eSim?
An eSim may not be necessary if you are travelling within the EU and your mobile provider already offers included EU roaming. Many smaller providers, like Smarty, ID Mobile and Lebara do this, so check to see what you already have included in your plan before you travel.
Of the 'big four' providers, only O2 currently includes EU roaming in its plans as standard. For more details on the providers that offer free EU roaming, read our guide on how to save on mobile roaming charges.
For those travelling further afield, an eSim can offer significant savings, as we'll explain below.
How much money could I save with an eSim?
Potential savings depend largely on where you travel, and how much data you expect to use. Ofcom estimates the average monthly mobile data use in the UK is around 10GB, so based on the assumption this will be enough for your holiday, we've put together some examples for three of the most popular holiday destinations outside the EU - the USA, Thailand and Mauritius.
These examples show that you could end up saving hundreds of pounds if you pick the right solution for roaming abroad.
Roaming pass add-ons
Some networks, primarily the 'big four' – EE, Vodafone, O2 and Three, offer roaming passes that can be added to your monthly bill and permit you cheaper roaming abroad. Costs vary, but we're using EE here as an example.
- USA or Thailand - 24-hour Zone 1 pass is £5 a day to use the usual plan allowance.
- Mauritius - 24-hour Zone 3 pass is £7.50 a day to use usual plan allowance.
Based on a two week holiday, and assuming your EE plan's data allowance is at least 10GB, this would cost £70-£105 to cover that average 10GB usage.
Data add-ons
Other networks may allow you to add a specific amount of data to use in certain countries. Prices again vary depending on amount and destination.
A 10GB 15-day roaming add on with Lebara for the US, Thailand and Mauritius would cost £20, £80 and £300 respectively, so it could end up being significantly more expensive than an add-on from EE.
How eSims compare
For cheaper roaming, look for an eSim deal. We checked the same destinations at two providers, but there are more to choose from, so make sure you shop around before deciding. We've listed some of the most popular at the end of this article.
The below prices are for 30 day packages, which means any unused data will expire after 30 days.
- Nomad passes to the USA, Thailand and Mauritius offer 10GB of data for £11.30, £9.04 and £33.90 respectively.
- Airalo's passes to these destinations, again for 10GB of data, cost £20.50, £9.50 and £47.
As you can see, it could end up being significantly cheaper to get an eSim with a good amount of data to cover your holiday.
How about Pay-as-you-go (PAYG) roaming?
One other option used to be relying on paying for roaming data as and when you use it, but this just isn’t affordable anymore. We checked the prices for two of the lowest cost Sim networks and the cost is prohibitive for anything more than the smallest of data uses.
Lebara charges £93/GB for USA, Thailand, Mauritius pay as you go roaming. Smarty is 10p/MB for USA and Thailand, which works out to over £100/GB, while PAYG roaming in Mauritius costs a staggering £5/MB, which would be over £5,000 for a single GB.
Will my phone number change if I use an eSim?
No, activating an eSim for travel will not change your phone number. You'll be able to use apps like WhatsApp as normal, as it is linked to your phone number, but uses the internet for communication.
This means after you have switched your phone to using the eSim for data, you’ll keep your existing number and account, but the internet connection will be provided by the eSim instead of your regular Sim.
Before making your trip, find out how to prepare your mobile phone for holidays abroad.
Where can I buy an eSim for cheap mobile roaming abroad?
As a growing market, new eSim providers are being launched all the time. There are so many options, depending on where you want to go and how much data you need.
You could start by checking out some of the larger, more established eSim providers, who all claim to provide for over 200 countries and destinations:
- Airlo – founded in 2019, it has over 20 million users and was an initial innovator in the travel eSim market.
- Nomad - started in 2020 by former Micosoft and Facebook engineers, Nomad is one of the biggest eSim providers.
- Saily - launched by Nord Security in 2024, the company behind NordVPN, Saily offers additional security features for peace of mind.
- GigSky - Gigsky was founded in 2010 and operates its own network in the USA, alongside selling eSims with partner networks around the world.
eSim comparison sites
Alternatively, there are a range of comparison sites that can help you find an eSim that's most suitable for your needs and budget:
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