What is eSimFLAG and how does it work?
eSimFLAG is Movistar/Telefónica's international eSIM for travelers: you buy the plan online, install a QR code on your cell phone before leaving, and upon arrival at your destination, the eSIM automatically connects to a local network with mobile data, without roaming and without touching your regular line's physical SIM.
The full name it appears under in app stores and on the official website is "eSimFLAG by Movistar." It does not replace your usual line: it is a second data line, exclusively for travel, that coexists on the same cell phone with your main SIM or eSIM. That's why you can continue to receive calls and messages on your usual number while using eSimFLAG data to browse, use maps, or send messages via WhatsApp.
If you've never used an eSIM and don't know where to start, it's a good idea to first understand the basics: what an eSIM is and how it differs from the physical card you already know.
Who is behind it: Is it from Movistar?
Yes. eSimFLAG is a brand of Telefónica (the group that owns Movistar), specifically designed for data connectivity during international travel. Telefónica described the service in its press room as a solution for planning data spending abroad without the typical surprises of traditional roaming.
"eSimFLAG is a 100% digital and prepaid service that allows users to plan their spending without surprises and pay only for the days they need."
This has practical implications for the traveler: by relying on Telefónica's network and the agreements it negotiates with partner operators in each country, eSimFLAG's coverage in a specific destination may vary depending on the strength of those agreements there. If you are interested in understanding this relationship with Movistar in more detail and what it means for pricing and coverage, there is a specific analysis in eSimFLAG and its connection to Movistar.
Coverage and destinations
According to eSimFLAG's own website (esimflag.com, accessed August 10, 2026), the service covers more than 170 countries spread across Europe, America, Asia, Africa, and Oceania. Europe appears to be the region with the most individual countries available within the same regional plan.
This figure is not fixed: eSIM operators constantly expand or reduce roaming agreements with local partners, so the exact number of countries covered may change between when you read this and when you make a purchase. The same applies to any provider, including PuraSIM, which is why it communicates its coverage as "more than 200 destinations" instead of a fixed number.
The correct way to check before traveling is not to rely on a blog (not even this one), but to type the exact name of your destination into the provider's coverage search engine on the day of purchase.
Pricing and plan structure
eSimFLAG sells its plans by days of validity with data that the brand itself describes as unlimited, rather than by fixed gigabyte packages. You pay for the number of days you will be traveling, and within that period, data consumption is not cut off by volume.
This "by day" model is different from that used by other providers, who sell blocks of gigabytes with a validity of several weeks, and you stop paying when you run out of data or the term expires, whichever comes first. Neither model is objectively better: by day is convenient if your itinerary is short and predictable; by gigabyte is convenient if your trip is long, with days of heavy use and days of almost none, or if you don't know the exact return date.
eSimFLAG's specific prices change by country, season, and active promotions, so we are not reproducing them here: any figure you see today may be outdated tomorrow. Always check them on the official page for the destination you are interested in, on the same day you plan to purchase.
| Feature | Day-based model (eSimFLAG) | Gigabyte-based model (PuraSIM) |
|---|---|---|
| Unit of sale | Days of validity | Gigabytes of data |
| What happens if you run out of data | Not applicable: the plan remains active until the days expire | You can recharge an additional plan from the website |
| Convenient if... | Your trip has fixed dates and constant use | Your consumption is irregular or you don't know the exact return date |
| Window to activate the eSIM | Variable depending on the plan purchased | 180 days from purchase |
How to install and activate it
The installation process is practically identical for any eSIM provider, because it depends on the cell phone's operating system (iOS or Android) and not on the brand selling the plan. You buy the plan, receive a QR code, scan it from your cell phone's settings, and it is installed—but inactive—until you arrive in the country where you will use it.
Before buying any eSIM, it's worth checking two things: that your cell phone model is compatible and that it is factory unlocked or unlocked by your current operator. We have a guide with the list of eSIM-compatible cell phones and a complete step-by-step guide to installing an eSIM without common errors, such as scanning the QR from the same cell phone where it will be installed (it doesn't work) or activating the plan before leaving home and losing days of validity without realizing it.
eSimFLAG indicates on its support site that it is available "24/7 every day of the week" via chat, WhatsApp, and email (esimflag.com, accessed August 10, 2026). This is a reasonable point of comparison against the support of any other provider: asking how many real contact channels it offers and if there's a human behind it, not just a bot.
Trustpilot reviews
eSimFLAG has a public profile on Trustpilot with reviews from travelers who have already used the service. We are not reproducing any scores or number of reviews here: these data change all the time, and if we copied them today, they might be outdated tomorrow. The correct way to consult them is to go directly to eSimFLAG's profile on Trustpilot on the day you are making your decision.
An aggregate score also doesn't tell you if your specific destination will work well. Before deciding on any provider, the most useful thing is to filter reviews by destination country and by recent date, rather than sticking to the overall average.
| Aspect | What users comment on |
|---|---|
| Installation and purchase | Process described as simple and straightforward |
| Connectivity in cities | Good coverage and speed in urban areas |
| Connectivity outside cities | Reports of connection drops and less stability in rural areas or while moving |
| Automatic activation upon arrival | Some cases of eSIM not automatically connecting to the local network upon landing |
This table summarizes patterns that are repeated in public reviews, not PuraSIM's own assessment of eSimFLAG: we have not tested the service ourselves, and it would not be honest to claim that we have.
Problems reported by users
The most frequently reported problem in public reviews is loss of connection when moving away from urban areas, along with isolated cases of eSIMs that did not activate automatically upon arrival at the destination and had to be activated manually. Neither of these issues is exclusive to this brand: they are the two most common problems with any travel eSIM, regardless of the provider, because they depend on the local network of the country, not just on the plan seller.
If you're concerned about losing signal halfway through your trip, it's worth reading up on what causes these failures and how to resolve them at the moment, not after you've already run out of data at an airport. We have a guide with the most common eSIM problems and how to solve them, applicable no matter what brand your eSIM is.
When a plan is advertised as "unlimited data," this usually refers to no gigabyte cap, but it doesn't always mean unlimited speed all the time. It's common for a fair usage policy to exist, which, after a high daily consumption, reduces speed (not access) for the rest of the day. If your trip depends on HD video calls or frequently uploading heavy video, it's worth checking that fine print in the terms and conditions of your chosen provider, whatever it may be, before assuming that "unlimited" means "without any limits at any time."
eSimFLAG vs. PuraSIM: an objective comparison
With the available and verifiable data from each side, this is how both options look side by side. The eSimFLAG column uses public information from its own site and Trustpilot, with the consultation date; the PuraSIM column uses only data that PuraSIM can support today.
| Feature | eSimFLAG | PuraSIM |
|---|---|---|
| Coverage | More than 170 countries (esimflag.com) | More than 200 destinations |
| Data model | By day, data described as unlimited | By gigabyte, adjusted to travel duration |
| Support channels | Chat, WhatsApp, and email, 24/7 (esimflag.com) | Email and WhatsApp, 24/7 in all languages |
| Activation time | Not specified on its public website | Approximately 1 minute |
| Activation period after purchase | Not clearly specified on its public website | 180 days from purchase |
| Brand behind | Telefónica / Movistar | PuraSIM (independent eSIM brand for travelers) |
We deliberately left blank the cells that we could not verify on eSimFLAG's public website at the time of writing, instead of filling them with a guess. We also did not include a review row: Trustpilot scores change frequently, and it is best to consult them directly on the platform, rather than copying them into an article that may become outdated.
If, after viewing the table, you are more interested in the gigabyte-based model with a long validity window for activation, we have provided a direct link to the available plans by destination below.
Which eSIM is more recommended?
There is no single answer valid for all trips: it depends on your itinerary, your cell phone, and how you typically consume data. As a general guide, a day-based plan with unlimited data like eSimFLAG's tends to be suitable for short trips with fixed dates, while a gigabyte-based plan with a wide window for activation—180 days from purchase, in PuraSIM's case—tends to be suitable if you buy in advance, your return date might change, or you want to keep the eSIM ready and activate it only when you land.
Before deciding, it's worth addressing two fundamental questions that don't depend on the brand: whether your cell phone works with eSIM and whether an eSIM is more convenient for you than your usual physical SIM. We have two guides that cover exactly that: eSIM vs. traditional roaming and what real costs each compares, without relying on any particular provider.
Frequently asked questions
Is eSimFLAG the same as Movistar Roaming?
Not exactly. eSimFLAG is a separate brand, specifically designed for purchasing prepaid travel data by the day, without relying on the roaming plan you have contracted with your usual operator.
Do I need to unlock my cell phone to use any eSIM?
You need your cell phone to have eSIM functionality enabled and, if you bought it financed with an operator, it must be unlocked. Check the list of eSIM-compatible cell phones before purchasing any plan, regardless of the brand.
Can I have eSimFLAG's eSIM and another provider's eSIM on the same cell phone?
Most modern cell phones with dual eSIM allow you to install several profiles and choose which one to use at any given moment, although the exact number of simultaneous profiles your model supports depends on the manufacturer. It's advisable to check your cell phone's specifications before buying more than one eSIM for the same trip.
What happens if my eSIM doesn't activate automatically when I arrive at my destination?
This is one of the inconveniences reported by users of various eSIM providers, not just one. It is usually solved by manually activating the data plan from the cell phone settings. We review the complete step-by-step process in the guide to common eSIM problems.
How long does it take for a PuraSIM eSIM to activate?
Activation takes approximately 1 minute once you arrive at your destination and confirm the plan from your cell phone.
How long after purchasing a PuraSIM eSIM can I activate it?
You have up to 180 days from the purchase date to activate it, so you can buy it well in advance and activate it only when you are about to travel.
Where can I check the most up-to-date reviews for an eSIM provider before purchasing?
Directly on Trustpilot or another review platform, filtering by recent date and, if possible, by destination country. A general average doesn't tell you how the service performed last week in the exact country you're traveling to.
Does PuraSIM offer phone support?
No. PuraSIM's support is via email and WhatsApp, available 24/7 in all languages handled by the brand.
Conclusion
eSimFLAG is a real option backed by Telefónica/Movistar, with broad coverage, a day-based data model that simplifies spending calculation, and a public profile on Trustpilot where you can review the latest opinions from other travelers. None of this data is invented: if anything has changed since we wrote this, the correct source to confirm it is the official eSimFLAG website and Trustpilot, not this article.
That said, if your travel style better suits gigabyte-based plans, a long window to activate the eSIM without missing the deadline, and 24/7 email and WhatsApp support in all languages, you can check the available options by destination in the PuraSIM international eSIM collection and compare the specific plan for your next trip, with prices and coverage updated at the time of purchase.
