An eSIM is a digital SIM card built into your phone that you activate remotely, without inserting anything physical — and for most travellers, it's now the easiest way to get affordable mobile data the moment you land, without hunting for a local SIM shop or paying your home carrier's roaming rates.
How an eSIM actually works
A physical SIM card is a small chip you swap in and out of your phone. An eSIM does the same job — identifying your phone to a mobile network and giving it a data plan — but it's a piece of software written into a chip that's already built into the phone. Instead of buying a physical card, you buy a "plan" from an eSIM provider, scan a QR code or tap a link they send you, and the plan installs itself onto your phone in a couple of minutes. You can hold several eSIM profiles on one phone at once (alongside your regular home SIM, physical or digital) and switch between them in your phone's settings.
For travel, the practical effect is: you can buy a data plan for the country or region you're visiting before you even leave home, have it ready to activate the moment you land, and avoid roaming charges on your home number for calls and texts if you keep your home SIM active alongside it. Having data working from touchdown is especially handy for smoothing over the small logistics of arrival — booking a taxi, finding your hotel, or checking transit options — the same practicalities covered in our guide to what immigration officers ask at the border just before you get there.
Which phones support eSIM
Most phones sold in the last few years support eSIM, but coverage isn't universal, and it's worth checking your specific model before relying on it:
- iPhone: XS/XR and later generally support eSIM; some region-specific models (notably certain phones sold in mainland China) do not.
- Samsung Galaxy: most flagship S and Z-series phones from around 2020 onward support eSIM, though carrier-locked or region-specific variants sometimes disable it.
- Google Pixel: Pixel 3 and later generally support eSIM.
- Other Android brands vary widely — check the specific model's specifications, since eSIM support is inconsistent even within a single manufacturer's range.
Your phone also needs to be network unlocked — tied to a carrier and locked can prevent installing a second, independent eSIM plan even if the hardware supports it. Check with your home carrier if you're not sure whether your phone is unlocked.
Connectivity is one of several practical layers worth sorting before departure alongside how you'll pay for things — see our guides to cash or card abroad and avoiding ATM fees for the money side of the same preparation.
When an eSIM beats roaming or a local SIM
Three real alternatives exist for staying connected abroad, and each suits a different situation:
- Home carrier roaming is the simplest — no setup at all — but is often the most expensive per gigabyte outside of plans that include specific international roaming zones (common within the EU for EU-based numbers, less common elsewhere).
- A local physical SIM, bought at the destination airport or a phone shop, is often the cheapest option for a longer stay in one country, but costs time on arrival, requires your phone to accept a physical SIM swap, and gives you a new number rather than keeping your home number reachable.
- An eSIM sits in between: typically cheaper than roaming, comparable to or a little more than a local SIM, set up in advance so it's ready the moment you land, and it doesn't require removing your home SIM — so your home number stays reachable for calls and texts if you leave it active.
eSIMs are strongest for multi-country trips (many providers sell regional plans covering, say, all of Europe or several Southeast Asian countries on one plan), short trips where hunting for a local SIM shop wastes valuable time, and anyone who wants data working literally from touchdown rather than after finding a shop in an unfamiliar city. They're a particularly natural fit for a longer overland trip crossing several borders, since a single regional plan can save re-shopping for a SIM at every crossing.
Setting one up before you travel
- Confirm your phone supports eSIM and is unlocked — check your phone's settings or the manufacturer's website.
- Choose a plan for your destination or region, sized to how much data you'll realistically use (streaming and video calls use far more than maps, messaging and browsing).
- Buy and install before you fly, ideally while still on reliable home WiFi — installation itself needs an internet connection, so it's much easier done in advance than scrambling at the airport.
- Leave it inactive until you land, or set it to activate automatically on arrival — most eSIM apps let you install now and start the data plan's clock only once you connect to the destination network.
- Check your phone's settings for which SIM handles data versus calls and texts, so you're not accidentally using your home SIM's expensive roaming data instead of the eSIM you just paid for.
What eSIMs don't do
An eSIM handles mobile data (and sometimes calls/texts on the new number, depending on the plan), but it doesn't replace your home number for anyone trying to reach you there — that's what keeping your home SIM active (with data roaming switched off to avoid charges) is for. It also doesn't replace the need to check whether your destination has good coverage in more remote areas; eSIM providers resell capacity from local networks, so coverage quality mirrors whatever those networks actually offer outside major cities.
Costs, in general terms
Data-only eSIM plans for a single country are typically priced per gigabyte or as a fixed data allowance for a set number of days, and multi-country regional plans usually cost more than single-country ones for a similar data allowance, reflecting the wider coverage. Costs vary a great deal by provider and destination, so it's worth comparing a couple of providers rather than assuming the first one you find is competitive — but as a general rule, even a generously sized eSIM plan tends to cost meaningfully less than a home carrier's standard daily roaming charge over the same trip. Our travel budget tool is a useful way to fold this into an overall trip estimate alongside transport and accommodation.
Frequently asked questions
Can I use an eSIM and my regular SIM at the same time?
Yes — this is the normal way to use one. Most phones support dual SIM with one eSIM and one physical SIM active simultaneously, letting you keep your home number reachable for calls and texts while routing data through the travel eSIM.
Do I need WiFi to install an eSIM?
Yes, to install the profile initially — this is why it's worth doing before you leave home, over reliable WiFi, rather than trying to do it for the first time on arrival with no working data connection yet.
What happens if I lose my phone with an active eSIM?
An eSIM is tied to the phone's hardware, so losing the phone means losing that eSIM too — the same practical risk as losing a phone with a physical SIM inside it. Most providers let you buy a new plan on a replacement device.
Are eSIMs reliable for emergency connectivity?
They're generally as reliable as the local network they run on, since eSIM providers resell existing network capacity rather than building their own. For genuinely remote areas with poor mobile coverage, no SIM solution — physical or digital — will fix a lack of underlying network coverage.
Sources and further reading:
- Check your specific phone model's eSIM compatibility on the manufacturer's official support pages before buying a plan.
- Compare current eSIM providers and regional plan pricing for your destination before departure.
- European Commission guidance on roaming rules for travellers moving within the EU.