Last updated: Wednesday 21 October 2026 (Europe/London).
Next update: when WorldSIM, Three, O2 or iD Mobile change their travel prices, and again before Christmas 2026.
By: Switch Editorial Team, Switch Squid Ltd
As of 21 October 2026, a travel eSIM is often the cheaper way to stay connected outside the EU this Christmas: WorldSIM’s International eSIM Pro, bought in the UK, works in 195+ countries with credit options of £15, £35, £50 and £100, while a UK network roaming add-on can cost £7 a day on O2’s Travel Bolt On or £42 for Three’s 7-day Go Roam Around the World Extra pass. The catch is that a travel eSIM’s data allowance varies by country, and some UK plans already include roaming in popular long-haul destinations, so check your own plan first. This SwitchSquid guide compares the two options for winter-sun and long-haul trips. We may earn a commission if you buy through links on this page; it doesn’t change the price you pay.
Sources: WorldSIM — International eSIM Pro, Three — roaming abroad, O2 — using your phone abroad and iD Mobile SIM only deals (all checked on 21 October 2026). Travelling within Europe? Our guide to EU roaming SIM only deals covers that.
WorldSIM International eSIM Pro — credit from £15
Works in 195+ countries with a UK number, with credit options of £15, £35, £50 or £100 when we checked on 21 October 2026
Up to 10GB, 20GB, 41GB or 85GB of data, depending on the country
Main limitation: data allowances vary by destination, and the smallest option has a separate eSIM charge, so check the basket total
What is the best travel eSIM for UK travellers outside the EU?
The best travel eSIM is the one that covers every country on your trip at a price below your network’s roaming charge. For trips beyond Europe at Christmas, such as Dubai, the USA, Egypt or Thailand, a multi-country eSIM that you top up once and keep for future trips is usually the simplest choice.
WorldSIM’s International eSIM Pro is one option. WorldSIM says it covers 195+ countries, includes a UK mobile number and free incoming calls and texts, and keeps working as long as you top up once within your airtime validity period, which extends it for 365 days. You can add a US number for an extra charge.
£15 credit: up to 10GB of data, depending on the country.
£35 credit: up to 20GB, depending on the country.
£50 credit: up to 41GB, depending on the country.
£100 credit: up to 85GB, depending on the country.
WorldSIM says the smallest option has a separate eSIM charge, while larger options include the eSIM free and selected purchases get up to 25% bonus credit. Check the total in your basket before you pay.
Is a travel eSIM cheaper than roaming with my UK network?
Often, yes, for long-haul trips, but not always. Some UK plans include roaming in destinations outside Europe, so check yours before you buy anything. If your plan doesn’t include your destination, daily charges and passes add up quickly over a two-week Christmas trip.
Option (checked 21 October 2026) | Cost | What you get | Watch out for |
|---|---|---|---|
WorldSIM International eSIM Pro | £15, £35, £50 or £100 credit | Up to 10GB, 20GB, 41GB or 85GB, depending on the country | Data allowance varies by destination |
Three Go Roam Around the World Extra pass | £17.50 for 3 days, £29.75 for 5 days, £42 for 7 days | Use your UK allowance in listed destinations | 12GB a month fair use policy |
O2 Travel Bolt On (Pay Monthly) | £7 a day | Your allowance in selected destinations | Standard rates outside the list |
O2 Volt or Plus plans | Included | Inclusive roaming in 27 destinations outside Europe (75 on Ultimate) | Only the listed destinations |
iD Mobile | Included | Roaming in 50 destinations | 30GB fair use limit; check the list |
What a 10-day trip could cost: on O2’s Travel Bolt On at £7 a day, 10 days is £70. On Three, a 7-day pass plus a 3-day pass is £59.50. WorldSIM’s £35 credit option gives up to 20GB, depending on the country, and any unused credit stays on the eSIM for your next trip if you keep it topped up. These are examples only, so check the rates for your destination.
Going long-haul this Christmas? Choose your WorldSIM credit
Larger credit options include the eSIM, and selected purchases get up to 25% bonus credit
Free incoming calls and texts, according to WorldSIM
Top up once within your airtime validity period to keep it for 365 days
Do I need a travel eSIM for Christmas in Dubai or the USA?
Not if your UK plan already includes that destination. O2 says Volt and Plus customers get inclusive roaming in 27 destinations outside Europe, and iD Mobile includes roaming in 50 destinations. Check the list for your exact country before you travel.
If your destination isn’t included, compare the cost of your network’s daily charge or pass with a travel eSIM. For a long trip, or a trip that covers several countries, a travel eSIM can work out cheaper. For a weekend away, a short roaming pass may be simpler.
How does a travel eSIM work with my UK SIM?
Most recent phones can hold a physical SIM and an eSIM, or two eSIMs, at the same time. You install the travel eSIM by scanning a QR code, then choose which line uses mobile data. Our guide eSIMs explained covers the basics, and eSIM vs physical SIM explains the differences.
Check your phone supports eSIM and isn’t locked to your network.
Buy and install the eSIM at home, while you have Wi-Fi.
Keep your main SIM switched on if you need bank security texts, but turn off data roaming on that line.
Set the travel eSIM as your data line when you land.
Keep an eye on usage, because the data you get depends on the country.
Should I switch to a SIM only plan with roaming instead?
If you travel abroad several times a year, a SIM only plan with roaming included might be better value than buying a travel eSIM each time. Look at which destinations are included and the fair use limit. Our eSIM only deals guide lists current plans you can set up without a physical SIM.
Not sure whether your current plan covers your Christmas destination? Ask Squid AI, SwitchSquid’s AI deal assistant, to compare the options for your trip.
Fit summary
Good fit for a travel eSIM: you are going outside Europe to a country your plan doesn’t include, or visiting several countries on one trip.
Stick with roaming if: your plan already includes your destination, or you are only away for a day or two.
Consider a new SIM only plan if: you travel abroad often and want roaming built in.
Important conditions
WorldSIM data allowances are “up to” figures and vary by country.
The smallest WorldSIM option has a separate eSIM charge; check the basket total.
Lifetime validity needs one top-up within the airtime validity period, according to WorldSIM.
Three’s Go Roam Around the World Extra passes have a 12GB a month fair use policy.
Your phone must support eSIM and be unlocked.
Final decision card
Destination included in your plan? Use your UK allowance and skip the eSIM.
Long-haul and not included? Compare a travel eSIM with your network’s daily charge.
Several countries or several trips? A reusable travel eSIM with credit is usually simplest.
Check WorldSIM rates for your destination
Check your phone supports eSIM and is unlocked
Install the eSIM at home before you travel
Compare with your UK plan’s roaming list first
FAQ
What is the best travel eSIM in the UK?
The best choice depends on where you are going and how much data you need. WorldSIM’s International eSIM Pro covers 195+ countries with £15, £35, £50 and £100 credit options. Compare the data allowance for your destination with your network’s roaming charge.
Is a travel eSIM cheaper than roaming?
For long-haul trips, it often is. O2’s Travel Bolt On costs £7 a day and Three’s 7-day pass costs £42. If your plan already includes your destination, roaming may cost nothing extra.
Can I keep my UK number with a travel eSIM?
Yes, if your phone supports two lines. Keep your main SIM switched on for calls and texts, and use the travel eSIM for data. Turn off data roaming on your main line to avoid charges.
Does a travel eSIM work in the USA and Dubai?
WorldSIM says its International eSIM Pro works in 195+ countries. The data you get depends on the country, so check the rates for your destination before you top up. Some UK plans include these destinations, so check yours too.
When should I install a travel eSIM?
Install it at home before you leave, while you have Wi-Fi. Then switch your data to the travel eSIM when you land. This avoids trying to set it up at the airport.
Do I need a travel eSIM for Europe?
Not usually. Many UK plans include roaming in Europe, and some charge a daily fee. Our EU roaming guide compares plans for European trips.
Last updated: Wednesday 21 October 2026 (Europe/London).
Next update: before Christmas 2026.
By: Switch Editorial Team, Switch Squid Ltd
