International roaming charges from UK carriers remain eye-watering. Even after Brexit forced a re-evaluation of EU travel policies, most UK operators reintroduced roaming fees for European travel — and outside Europe, charges of £5–£10 per day are standard. A two-week holiday using your UK number for navigation, messaging, and the odd Instagram story can easily add £70–£140 to your phone bill.
Travel eSIMs solve this cleanly. For the same two weeks, you're looking at £6–£15 total. The technology has matured, the providers are reliable, and setup takes under five minutes. This guide covers everything: what an eSIM is, whether your phone supports it, the four best providers for UK travellers, and a step-by-step setup guide.
What Is a Travel eSIM?
An eSIM (embedded SIM) is a virtual SIM card built directly into your phone's hardware. Rather than a physical card you slot in, you download a profile onto the eSIM chip via a QR code. The entire process takes about three minutes and can be done at home before you leave.
Once installed, a travel eSIM gives you a local data connection in your destination country, charged at local data rates rather than UK roaming rates. You keep your UK number active on your physical SIM — so calls and texts still come through — while all your data (maps, apps, social, streaming) runs through the cheaper eSIM plan.
Key benefits at a glance: No physical SIM card to buy or lose. Install from home before departure. Keep your UK number active. Switch between plans for different countries. Typically 70–90% cheaper than roaming.
Does Your Phone Support eSIM?
eSIM support is now standard on most phones released in the last 3–4 years. Here's a quick compatibility guide:
Apple iPhone
iPhone XS and later (2018+). iPhone 14 US models are eSIM-only with no physical SIM tray. All modern iPads with cellular also support eSIM.
Samsung Galaxy
Galaxy S20 and later, Galaxy Z Fold/Flip range, Galaxy Note 20+. Most flagship Samsung devices from 2020 onwards.
Google Pixel
Pixel 3 and later (all models). Pixel phones tend to have excellent eSIM support and straightforward installation.
Other Android
Most flagship Android phones from 2021+ support eSIM. Check Settings > About Phone > SIM Status, or search "[your phone model] eSIM support".
Not supported
Budget Android phones under ~£150. Most phones from before 2019. Some carrier-locked devices may have eSIM disabled by the network.
Check before you buy
If unsure: Settings > Cellular (iPhone) or Settings > Connections > SIM Manager (Samsung). If you see "Add eSIM" or "Add Cellular Plan", you're good.
Network lock check: If you bought your phone directly from a UK carrier (not unlocked), it may be locked to that network and block eSIM activation from third-party providers. Contact your carrier to check — most unlock phones for free after 6–12 months.
eSIM vs Roaming: The Real Cost Comparison
| Scenario | UK Roaming (typical) | Travel eSIM (typical) | eSIM saving |
|---|---|---|---|
| 1 week in Europe (3 GB data) | £25–£40 | £3–£8 | Up to 87% less |
| 2 weeks in USA (5 GB data) | £70–£100 | £10–£18 | Up to 86% less |
| 1 week in Thailand (3 GB data) | £35–£70 | £4–£9 | Up to 89% less |
| 2 weeks in Australia (10 GB data) | £70–£140 | £12–£22 | Up to 91% less |
Roaming costs based on typical UK carrier daily/weekly add-on packages as of 2026. eSIM prices from Airalo, Yesim and Holafly. Actual prices vary by plan and country.
Top eSIM Providers for UK Travellers
Coverage across 150+ countries with genuinely competitive data rates. Data-only plans (no calls or texts, which is all most travellers need). Pricing starts from around £2.99/week for Europe. The app is clean, activation is fast, and they offer multi-country regional plans that cover all of Europe or all of Asia on a single eSIM profile — useful if you're moving between countries.
Built by the team behind NordVPN, Saily launched in 2023 and has grown quickly on the back of NordVPN's distribution. The pricing structure is clear and honest — no hidden activation fees or confusing data bundles. Cover for 150+ countries, with plans typically in the £3–£10/week range depending on data allowance and region. Customer support is responsive given the parent company's track record.
Airalo is the largest eSIM marketplace — rather than offering its own network, it aggregates plans from local operators in 200+ countries. This means you can often find the cheapest available local plan for your specific destination. The trade-off is more complexity: you're choosing between multiple providers per country rather than a single curated offer. Best for savvy travellers who want maximum choice and lowest possible price.
Holafly's defining feature is unlimited data plans — not capped in GB, charged by day or duration instead. If you're a heavy data user (think: working remotely while travelling, streaming frequently, or using your phone as a hotspot), unlimited plans remove the anxiety of watching your data. Prices are higher than data-capped alternatives, but the peace of mind is valuable. Coverage in 160+ countries.
How to Set Up a Travel eSIM: Step by Step
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Choose your provider and plan. Select a provider above, visit their website or app, choose your destination country (or regional plan), and the data amount and duration you need. For most holidaymakers, 3–5 GB for 1–2 weeks is plenty. If you're using Google Maps all day, add a bit more.
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Purchase and receive your QR code. Pay online and you'll receive an email with a QR code (and usually instructions). Do this before you travel — you need a working internet connection to scan the QR code, and doing it at home is far easier than hunting for airport Wi-Fi.
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Install the eSIM profile on your phone. On iPhone: Settings > Cellular > Add eSIM > Use QR Code — point your camera at the QR code. On Android: Settings > Connections > SIM Manager > Add eSIM > Scan QR Code. The download takes 30–60 seconds. The eSIM will appear as a second line on your phone.
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Don't activate until you land. After installation, most plans let you choose when the data period starts. Set it to activate on arrival rather than immediately — so your 7-day data clock starts when you actually land, not when you install it at home two days before.
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Set data routing at the airport. Once you land, switch your default data line to the eSIM. On iPhone: Settings > Cellular > Default Line for data. Keep your UK SIM set to receive calls/texts but not data. Enable "Wi-Fi Calling" on your UK SIM if you want to receive calls over Wi-Fi without using roaming.
Pro tip: Download your offline maps (Google Maps or Maps.me) before you leave the UK. A downloaded map of your destination uses zero data for navigation — your eSIM data lasts significantly longer when maps are offline.
Common Questions
Can I make phone calls with a travel eSIM?
Direct answer. Most travel eSIM plans are data-only — they don't issue you a phone number for traditional calls or texts. You keep your UK number on your physical SIM (or your existing primary eSIM) for calls and SMS, and use the travel eSIM for data only.
For voice calls abroad, the practical solution is to call over data using WhatsApp, FaceTime Audio, Telegram, Signal or Skype — all free, all high-quality on a decent connection, and all working identically whether you're in the UK or in Bangkok. Set your dual-SIM phone so the travel eSIM is the default for cellular data and your UK SIM stays active for receiving calls and SMS, but disable data roaming on the UK SIM to avoid the £5–£8/day operator roaming charge.
The maths to run. A 7-day Europe trip on a 5GB Airalo eSIM costs ~£11. Receiving a few inbound UK calls on your physical SIM at standard EU roaming (free for most UK contracts under fair-use) costs nothing. The same trip with operator roaming for data alone costs £35–£56. Net saving: £24–£45.
Key fact: Voice-over-WhatsApp call quality on a 4G/5G eSIM data connection is indistinguishable from a normal cellular call to anyone you ring — and free, both ways, anywhere with coverage.
Will an eSIM work in both directions on a multi-country trip?
Direct answer. Yes — regional eSIM plans from Yesim, Saily, Airalo, Holafly and others cover multiple countries on a single profile. A Europe-wide plan will automatically switch local networks as you cross borders, with no manual reconnection needed.
Always check the specific country list before buying. "Europe" plans usually cover the EU plus the UK, Switzerland, Norway and Iceland; some include Turkey, some don't. "Global" plans cover 100+ countries but exclude a handful of high-cost markets (Cuba, Iran, North Korea, sometimes Russia). Multi-country trips from the UK to Croatia via Italy and Slovenia, for example, work seamlessly on a single Europe plan; a UK→Morocco→Spain trip needs either a global plan or two regional ones because Morocco isn't in most "Europe" plans.
The maths to run. A 14-day three-country Balkans trip on a single 10GB Airalo Europe plan: £20. The same coverage on three single-country plans: £8 per country × 3 = £24, plus the hassle of swapping. The regional plan is almost always cheaper and always less work.
Key fact: Buy a regional plan (Europe, Asia, Latin America) rather than single-country plans for any trip touching more than two borders — pricing favours the regional option once you cross the second border.
What happens when I run out of data?
Direct answer. Most providers let you top up through their app or website using the same payment method, and your existing eSIM profile stays installed. Alternatively, buy a fresh plan — the new plan stacks on top of the old one with no setup repeat.
The major providers (Airalo, Yesim, Saily, Holafly, Nomad) all push a real-time data balance into their app and will warn you at 80% and 95% consumption. Top-ups process in 1–3 minutes and the new data is available immediately. If you're on a remote connection or the app fails, buying a brand-new plan from a different provider works as a backup — eSIM profiles can be installed in parallel and you can switch between them in your phone's cellular settings.
The maths to run. Top-ups are usually slightly more expensive per GB than the original plan (they're priced for the convenience). A 5GB Europe plan at £8 is £1.60/GB; a 1GB top-up on the same plan typically runs £2.50–£3.50. If you're regularly running out, buy the next size up next time rather than topping up — it's cheaper per GB.
Key fact: Set the in-app warning at 75% rather than the default 80%, and you'll have time to top up calmly rather than at 5% with no signal in a taxi.
Is a travel eSIM safe and secure?
Direct answer. Yes. eSIM profiles are encrypted, tied to your device's secure element hardware, and remotely deletable if your phone is lost. The data connection itself is identical to a physical SIM — same security model, same encryption.
The technical details: eSIM profiles use the same SIM toolkit, same authentication, and same network-level encryption (AES) as a physical SIM. The profile lives in your phone's embedded UICC (eUICC) chip, which is a tamper-resistant secure element separate from your main system memory. If your phone is lost or stolen, you can delete the eSIM profile remotely from the provider's app or website — and the device itself can no longer use that profile even with a SIM swap.
The maths to run. Standard mobile-data security advice applies regardless of SIM type: use HTTPS sites only, use a reputable VPN on public Wi-Fi, enable two-factor authentication on financial apps. The eSIM doesn't add or remove risk. The risks worth thinking about are the eSIM provider's own data handling — pick providers with clear privacy policies (Yesim, Saily, Airalo all publish theirs).
Key fact: An eSIM is at least as secure as a physical SIM, and arguably more so — it can't be physically stolen and slotted into another device, and a remote-wipe through the provider blocks reuse on a thief's handset.