Smartphone with SIM card and holder

eSIMs for Travel: A Great Option, But They Come With a Catch

By Patricia Rey Mallén Get Connected18 Comments

For calls, texts, and data while traveling, we’ve long recommended making sure your phone is ready for your trip and then picking up local SIM cards in each new country.

They’re the best way to stay connected internationally, since you’ll typically get better rates and/or speeds than when you’re roaming, plus a local number for people to call you on.

However, as much as we love local SIMs, they’re not without their problems. They can be time-consuming and difficult to buy due to language and technical issues, and you have to mess around with swapping little pieces of plastic in and out of your phone.

Since you often can’t get them until you’re physically in a country, you can also find yourself disconnected during those vital first few hours after arrival unless there’s a store at the airport or station. For those without dual-SIM phones, they also mean losing access to your usual number while you’re away.

Wouldn’t it be nice if there was a way to simply turn on your phone once you arrive, and connect to a local carrier at something approaching local rates instead? Well, there is, and surprisingly, it’s already been on the market for a few years. Welcome to the eSIM.

If it doesn’t ring a bell, it’s probably because you haven’t been following Apple’s phone announcements. eSIM support has been built into the iPhone for several years now, bringing what was a niche product into the mainstream.

In theory, the technology should be a boon for travelers, and make staying connected overseas much cheaper and easier. That can be true, at least for some travelers, but things are still a bit more complicated than they should be.

So What Is eSIM, Anyway?


First things first: the “e” doesn’t stand for “electronic.” Unlike most examples that come to mind (e-mail, e-card, e-bill, e-whatever), eSIM stands for “embedded Subscriber Identity Module.” That tells you a lot about what this thing actually is.

A piece of hardware built into an electronic device, an eSIM acts like a traditional physical SIM card, identifying and authenticating a device on a cellular network. Since it’s embedded, the eSIM always stays inside the device. There’s no need or ability to remove it.

What does this mean in practical terms? Easy: a device with an eSIM will be ready to use once it is turned on and activated on a network. You don’t have to find a store, buy a piece of plastic, or fumble around with the SIM slot. Sounds amazing, right?

Which Devices Support It?


More and more devices are starting to support eSIM, helped by Apple including it in every iPhone since the XR and XS models. In fact, if you live in the US or Canada and have bought the latest iPhone 14, eSIM is the only option you’ve got: there’s no physical SIM slot in the North American model.

It’s also been available in the Apple Watch since late 2017, along with recent iPad models. Several of our current top mid-range smartphone picks offer dual SIMs: one physical, one eSIM.

Apple wasn’t first out of the gate, however. Samsung bundled an eSIM into the Gear S2 smartwatch back in 2016, and its Galaxy and Note devices more recently, while Google has included one in all of its Pixel smartphones since the Pixel 2 in 2017.

Other Android vendors are also starting to include it, at least in certain models, and even some Windows laptops have the option of using an eSIM to get connected when there’s no WiFi available or you can’t rely on it.

Of course, the hardware is only half the story. For eSIM technology to work, cellular providers also need to support it on their networks. That’s where things get tricky.

Where Are eSIMs Available?

The number of countries where you can enable local eSIMs is slowly growing. From 10 countries at launch, the list has now grown to over 60.

In many of those countries, though, eSIMs aren’t supported by all providers. In the US, for instance, T-Mobile, AT&T, and Verizon offer it, but most of the resellers like Boost and Cricket don’t.

In the UK, EE, O2, and Vodafone include an eSIM option, but Three and virtually all of the resellers don’t. The surge in eSIM-enabled devices is getting more networks to jump on board, but it’s a slow process.

Most carriers are scared of the technology, since eSIM makes it far easier for existing customers to change providers. When a better deal is available right there on the device, with no need to do any real research or go into a store, you can bet more people will switch, more often. That’s the last thing a mobile company wants.

That’s one of the reasons why, right now, even the carriers with eSIM support almost universally don’t offer it on a prepaid plan. T-Mobile in the United States is the only major exception to the rule. This reluctance is far from ideal for travelers, and another hurdle in the way of widespread adoption.

If eSIM somehow takes off anyway, that fear of losing customers could provoke price wars, with providers battling over who can offer the best deals in a bid for market share.


Are eSIMs Really The Future for Travelers?

At first sight, eSIM sounds like a dream come true for travelers. Who wouldn’t want to turn up in a new country, turn on their phone, and connect to a network with a couple of taps before even leaving the airport?

The technology sounds like it will bring nothing but benefits — but is that really the case?

When it comes to convenience, there’s little doubt eSIMs can make the process of joining a carrier much easier than it is today. Simply purchase a plan from your device, follow any authentication instructions, choose a payment method, and you’re done. There’s no need to leave your home (or the airport) to do it.

This is ideal for constant travelers, allowing them to stay connected no matter how often or how suddenly they change locations. Even for those with a home base, though, it makes travel easier, especially for those regularly going back and forth between two countries.

Business travelers or expats who visit their home country regularly, for instance, can maintain two profiles on their eSIM and switch between them at will. Other than the obvious convenience, it means there’s no chance of losing a physical SIM card when it’s not being used. Not that we know anyone who’s done that. Ahem.

Replacing physical SIMs with eSIMs also saves space inside the device. This can be used for other features, extra battery life, or just making the hardware a little smaller.


It also helps with waterproofing, with one less slot for liquid to enter. There can also be minor savings in production costs, which may or may not be passed onto the customer.

The problem, of course, is that none of these potential advantages amount to much until there’s widespread support from carriers, including prepaid options. Until then, it’s great if you happen to be in the right country, but far from something you can rely on using worldwide.

So what’s the best approach?

What’s the Best Way to Use an eSIM When Traveling?

Use an International eSIM

Where local carriers have been slow to offer prepaid eSIM options to travelers, international SIM card providers have seen an opportunity. Companies like Airalo, AloSIM, and SimOptions offer eSIM-based data services in many countries and regions around the world, enabled via a QR code or app.

They’re typically not quite as cheap as local data packages, but Airalo in particular often comes close, especially for lighter data use or shorter stays. We often use the company’s eSIMs when first arriving in a country, or for our entire trip if we’re only there for a week or two.

To that end, we recently put together a detailed guide to the best international eSIMs, testing a whole bunch of them to come up with recommendations for the best (and worst) of the current crop.

Switch Your Usual Number Across

As an alternative, since almost all phones with eSIMs currently have a physical SIM slot as well, the best way for many travelers to use the embedded SIM may actually be at home. If you live in a country where carriers have eSIM support, see if it makes sense to switch across.

If so, that frees up the physical SIM slot for use while traveling without losing access to your home number. This makes the most sense for people who spend several weeks or months in a country and want a local SIM to access the cheapest rates.

All things considered, then, eSIM is a promising technology, but not the holy grail for connected travelers as yet. It needs better support, both in phone hardware and from cell carriers, before that day comes.

One day in the future, it’ll be a truly mainstream option. Until then, we’ll just go with international eSIMs , or stick with the tried, true, mildly-frustrating approach we’ve used for years: growing our endless collection of local SIM cards instead.

Images via Pexels (smartphone with SIM card and holder), Apple (photo of Lego, Apple store), Tinh tế Photo (Google Pixel 2), Gauthier Delecroix (making a phone call)

About the Author
Patricia Rey Mallén

Patricia Rey Mallén

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A roaming writer and tech enthusiast, Patricia has been wandering the globe for 10-odd years. A passionate Apple lover, she is familiar with Genius bars from Sydney to Reykjavík to Mexico City, and only vaguely remembers life before the internet.


  1. Avatar

    The article mentions that you cannot have both the eSIM and physical SIM active at the same time. However, on my Apple iPhone XS Max, both are always active. That is, for instance, if I am on a call via my eSIM, I can receive incoming calls to the number associated with my physical SIM. I see the standard options about accepting + hold, declining, etc.

    1. Dave Dean

      Apple’s support documentation says that you’ll only receive concurrent calls when you’re using iOS 13 and have Wi-Fi calling enabled and active for the number that’s not currently in use. If not, the second line will still go to voicemail whenever you’re on an existing call.

      It’s a slight improvement from iOS 12, but still a long way from true dual active support. In either case, you’ll also only get cellular data on one SIM at a time.

      1. Avatar

        Dave, please clarify. It’s 2022 now and we’re now using iOS 15 (soon 16) for iPhones.

        I have a physical SIM and an eSIM. As part of the set-up, I am asked which line do I want to use for voice (calling). The other line can be used for DATA or voice as far as I can tell. In my situation, I have the eSIM as data only.

        I’m not sure how Wi-Fi calling comes into this mix. Most people have no idea what Wi-Fi calling is. While Wi-Fi calling doesn’t need to use cellphone towers, you need to have a SIM or eSIM installed. The best thing to do when travelling is to enable Airplane mode and then enable WI-FI. If your SIM provider offers Wi-FI calling and you have set it up (correctly) you can enjoy calling to and from home using this method while oversees.

        It’s very true that virtually every mobile provider worldwide will not offer eSIM to prepaid (pay as you go) customers. They will sell/provide you with a physical SIM.

        Furthermore, in Asia for instance, many people who have Android phones are able to receive calls concurrently with DUAL SIM (physical) SIM phones.

      2. Dave Dean

        Hi Sammy,

        Regarding Wi-Fi calling, I agree that most people don’t know what it is. That said, I just took a look at that support link I posted back in 2019 – while it’s definitely been updated a few times since then, it still says the following:

        With iOS 13 and later, when you’re on a call, if the network provider for your other phone number supports Wi-Fi calling, you can answer incoming calls on your other number.

        So it looks like that’s still a requirement from Apple’s perspective, at least currently.

        I hope that’s what you were asking about – if not, just let me know what you wanted clarification on and I’ll try to help.

  2. Avatar

    In Portugal you can use eSim with a prepaid Vodafone. Not sure about NOS or Altice but in my case since I was converting a physical sim to an e-sim it took around 15 minutes on the store.

  3. Avatar

    Been using Airalo for a while now and it’s the best esim I’ve found . Travel a lot for work , places like the Caribbean can be quite expensive normally for roaming but nice data packages on Airalo.

  4. Avatar

    Some providers require that you activate the eSIM via SMS. But they mandate that this has to be done locally, not when on roaming. This could be a major inconvenience, at least in my option.

  5. Avatar

    So, I have an AT&T iphone max pro and want to add an esim in Australia. Do I need to unlock the phone first?

    1. Dave Dean

      Assuming it’s not unlocked already, then yes, you do. If your phone is fully paid off and your account is in good standing, you should be able to do so here.

  6. Avatar

    My iPhone 11 has been switched to an eSIM, leaving the physical slot open as mentioned in the article. Will UK carriers recognize my phone on their networks given that some of them haven’t adopted eSIM “technology” yet? Does this mean that a phone with an eSIM will still work fine on their network (while roaming) … but they just don’t sell eSIMs themselves?

  7. Avatar

    I am new to eSIMs but can’t wait to get one for an upcoming
    trip. Should I activate it before I leave the US or once I land in France?

    1. Dave Dean

      It depends slightly on which company you use, but in general it’s easier to activate it before you leave the US and then disable it until you get to your destination. That way it’ll work immediately on your arrival, when you’re quite likely to need it. Each company should provide detailed instructions about this, though.

      I discussed the detail of this in my Airalo review after using that service a couple of months ago — it might be worth a read to see how it worked.

    1. Dave Dean

      Thanks, updated the text. They still aren’t offering it for prepaid/PAYG customers, so it’s not useful for inbound travelers, but they’re hardly unique in that regard!

  8. Avatar

    I think eSIMs for travel have a LONG way to go before they are practical. First, they are insanely expensive in more out of the way countries (most of Africa, for example). I spend quite a bit of time in Africa, so that is already a problem. Second, they require an active wifi connection to setup. More and more often the ‘free’ wifi at airports and other public locations requires an SMS to activate, which if you don’t want to use roaming to receive leaves you in a catch 22, you can’t setup/install your eSIM on the go, you have to do it prior to leaving home. Which is fine, unless you end up making an unexpected stop (like happened to me last week). Moreover, if you run out of credit on that sim you can’t top up without wifi, whereas most physical sim networks allow you to dial into to a top up system even if you’re out of credit.

    That Apple is dropping the physical SIM tray in their new phones is a problem for me, I’ll be hanging onto my old SE for as long as I can, or buying a Euro spec iphone that still has the SIM tray.

    I am surprised that these flaws are not more widely written about.

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