How good is the Kolet eSIM?
Kolet is a French-originated travel eSIM that works with a single installation and data top-ups per country or region from its application, with reported international coverage in a large number of countries. It is a project with serious funding behind it, although it requires using its app for each purchase and does not offer unlimited data plans.
If you're looking for "Kolet eSIM," you probably already know what an eSIM is and want to know if this particular brand is suitable for your next trip. Before comparing, it's worth understanding how the company is structured and how its product works in practice, because its model (a single reusable eSIM for the whole world, with top-ups within an app) is different from other providers that sell a new eSIM profile for each destination.
In this article, we only review information published by Kolet and specialized media, with each data point and its source and consultation date. We do not include reviews, ratings, or customer figures: these things change all the time and cannot be independently verified at the time of publication.
Who is behind Kolet?
Kolet was founded in January 2024 in Paris by Eduardo Ronzano, Anne-Carole Cöen, Jérémy Gotteland, and Mehdi Chraibi, as reported by EU-Startups in its coverage of the company's funding round (eu-startups.com, June 2025 article, accessed August 5, 2026).
The company has raised two investment rounds: first, a seed round of 5 million euros with European funds Daphni and 9900 Capital, and then a Series A of 8.6 million euros again led by Daphni, with the participation of Peter Kern (former CEO of Expedia Group) and Jon Gieselman (former VP of Marketing at Apple), plus 1 million euros non-dilutive contributed by Bpifrance, the French public investment bank (eu-startups.com and siliconcanals.com, accessed August 5, 2026).
Kolet also announced an integration with Air France-KLM's Flying Blue frequent flyer program, which allows its members to access Kolet data offers in certain destinations (news.klm.com, accessed August 5, 2026). This is relevant because it explains why it is common to find Kolet's name within airline apps or loyalty programs, and not just in app stores.
How does the Kolet eSIM work?
Kolet's model relies on a single "universal" eSIM that is installed only once on the phone and then topped up with data according to the country you travel to, without the need to install a new profile every time (kolet.com/how-it-works, accessed August 5, 2026). On its own website, Kolet summarizes its proposal as follows:
"Install once, use forever." This is how Kolet describes, in English, the central promise of its universal eSIM (kolet.com/how-it-works, accessed August 5, 2026).
In practice, this means that after installing the eSIM profile for the first time, your subsequent data purchases —for the same trip or a future one— are managed by buying "packs" from within the app, without repeating the installation process. This is a different approach from eSIMs that sell a specific profile per destination, where each purchase usually involves scanning a new QR code. If you have never installed an eSIM, it is advisable to first review how this process is generally done before comparing specific brands: you can see the step-by-step in our eSIM installation guide.
A little-known detail of the Kolet system: unused data from a pack (above 1 GB remaining) is not lost upon expiry but is automatically converted into an internal credit called "Koins," which you can use in your next in-app purchase (help.kolet.com, article "What is Kolet's universal eSIM?", accessed August 5, 2026). In practice, this changes the purchasing logic: since the leftover is recycled, buying the largest pack "just in case" carries less weight as an argument, because what is left over is not entirely lost anyway; it is more convenient to buy close to what you will actually consume on that trip and let the Koins system absorb the difference.
In which countries does the Kolet eSIM have coverage?
Kolet reports coverage in 190 destinations worldwide, distributed approximately as follows: 43 in Europe, 39 in Asia, 23 in America, 44 in Africa, and 8 in Oceania, according to the breakdown offered by the MyBestSim review (mybestsim.com, accessed August 5, 2026). Kolet itself describes its coverage as oriented towards "major travel destinations, including the United States, Europe, Australia, and regions of Asia and South America" (kolet.com, accessed August 5, 2026).
It is important not to confuse "destination coverage" with "network coverage within each country": Kolet is not its own network operator, but rather works with different local operators in each market (kolet.com, accessed August 5, 2026), just like most travel eSIMs do. If you want to understand the difference between this eSIM data model and your local operator's traditional roaming, we explain it in detail in our guide on eSIM vs. roaming.
What do you need to install the Kolet eSIM?
To use Kolet, you first need an eSIM-compatible phone. According to the Holafly review, Kolet is compatible with iOS 15.1 or higher and with relatively recent Android models with eSIM, such as the Pixel line or the Galaxy S20 onwards (esim.holafly.com, accessed August 5, 2026). If you are unsure whether your phone supports eSIM, you can check our list of eSIM-compatible phones before purchasing any plan, regardless of the brand.
The second requirement, and the one that most distinguishes Kolet from other providers, is that you need to download its app: it is the mandatory channel to install the eSIM profile, purchase data packs, and monitor your consumption (help.kolet.com, article "What is an eSIM?", accessed August 5, 2026). According to the brand's public documentation, there is no purchase option that avoids going through the app.
Finally, you need an internet connection (Wi-Fi or other data) at the time of installing the profile for the first time, which is common to practically all eSIMs on the market, as installation is a digital process.
How much does the Kolet eSIM cost?
Kolet does not publish a fixed and unique price list: its plans vary by destination, and they must be consulted within the app or in the destinations section of its website (help.kolet.com, article "What are the prices?", accessed August 5, 2026). Even so, both Kolet and specialized reviews provide concrete references that serve to give you an idea of the price range.
According to its own website, Kolet's plans have a low entry price within the travel eSIM category (kolet.com/how-it-works and mybestsim.com, accessed August 5, 2026). The Holafly review, for its part, organizes its catalog by destination and data volume, with this structure:
| Destination | Data | Validity |
|---|---|---|
| United States | 1 GB | 30 days |
| United States | 3 GB | 30 days |
| United States | 5 GB | 30 days |
| United States | 10 GB | 30 days |
| United Kingdom | 1 GB | 30 days |
| United Kingdom | 5 GB | 30 days |
| United Kingdom | 10 GB | 30 days |
*Prices reported in the Kolet review published by Holafly (esim.holafly.com), accessed August 5, 2026. Kolet changes prices by destination and over time: always confirm the current price within its app or website before paying.
Taking the set of Kolet plans, the MyBestSim review summarizes the catalog in packages of between 1 GB and 20 GB, and validity of between 30 and 365 days depending on the package (mybestsim.com, accessed August 5, 2026). If you prefer an eSIM with international coverage and without the need to install a separate app, you can check the plans in our international eSIM collection.
Which company offers free eSIMs?
Kolet offers a promotion of 1 GB of free data, intended as a service trial, valid for 2 days from the moment you start using it, and is usually distributed through partners such as airline programs or travel deals pages (help.kolet.com, article "When does my data plan start, and what is the validity?", and turbopass.com, accessed August 5, 2026). After using this free trial, Kolet reports that a 10% discount applies to the next in-app data purchase (turbopass.com, accessed August 5, 2026).
It's worth reading the fine print of any "free eSIM" offer, regardless of the brand: they are usually small amounts of data (here, 1 GB), with a short validity (2 days in this case) and intended as a lure for you to start using the app or service, not as a real alternative to a data plan for the entire trip.
If your priority is not a specific promotion but having a reliable eSIM for the entire trip, with support available while you are away, at PuraSIM we offer activation in approximately 1 minute and 180 days from purchase to activate the eSIM when you need it, with 24/7 support in all languages by email and WhatsApp.
Objective advantages and limitations of Kolet
Advantages
Among Kolet's advantages, documented in the sources cited in this article, are: a single reusable eSIM for multiple trips without reinstalling the profile each time (kolet.com, accessed August 5, 2026); a system that converts excess data into credit ("Koins") instead of losing it (help.kolet.com, accessed August 5, 2026); small starter packages to try the service; and significant financial backing, with investors such as Bpifrance and former Expedia and Apple executives on its cap table (eu-startups.com, accessed August 5, 2026).
Limitations
Among the objective limitations: Kolet does not offer unlimited data plans in any destination (esim.holafly.com, accessed August 5, 2026); it relies exclusively on its own app, with no option to purchase or install outside of it (help.kolet.com, accessed August 5, 2026); and the MyBestSim review notes that initial activation can be problematic in some cases and that changing countries within the app is sometimes complicated (mybestsim.com, accessed August 5, 2026). If you are interested in a more general overview of the typical drawbacks of any eSIM (not just Kolet), we cover it in our guide on common eSIM problems.
Kolet vs. other travel eSIMs
Before deciding, it helps to compare the same criteria between Kolet and other travel eSIMs based on verifiable data, not opinions. This table combines what the cited sources report about Kolet with the data that PuraSIM confirms about itself:
| Criterion | Kolet | PuraSIM |
|---|---|---|
| Destinations with coverage | 190 destinations (kolet.com, accessed Aug 5, 2026) | More than 200 destinations |
| Support channel | In-app chat, website, and WhatsApp, as reported by Holafly (esim.holafly.com, accessed Aug 5, 2026) | 24/7 in all languages via email and WhatsApp |
| Purchase validity | Plan starts when first MB is used; validity of 30 to 365 days depending on the package (help.kolet.com and mybestsim.com, accessed Aug 5, 2026) | 180 days from purchase to activate the eSIM |
| App requirement | Mandatory: all installation and purchase goes through the Kolet app (help.kolet.com, accessed Aug 5, 2026) | Activation in approximately 1 minute |
The objective reading is that both options cover a comparable number of destinations and offer a support channel via WhatsApp. The most practical difference lies in the purchase model: Kolet centralizes everything in its own app with an internal credit system, while other eSIMs on the market—including PuraSIM—give more time to activate the plan after purchase. If you also want to understand how an eSIM differs from a traditional physical SIM before deciding between providers, we explain it in our guide on eSIM vs. physical SIM.
Frequently asked questions
Is Kolet a reliable company?
It is a company registered in France, founded in January 2024, with two investment rounds raised (5 million euros and then 8.6 million euros) and institutional investors such as Bpifrance (eu-startups.com, accessed August 5, 2026). This does not replace your own judgment when reading its terms of service before purchasing, but it does indicate that it is not an improvised project.
Do I absolutely need to install the Kolet app?
Yes. According to Kolet's public documentation, the app is the mandatory channel to install the eSIM profile, purchase data packs, and monitor your consumption; there is no alternative purchase option outside the app (help.kolet.com, accessed August 5, 2026).
What happens to the data I don't use from a Kolet plan?
If you have more than 1 GB left when the pack expires, Kolet converts it into an internal credit called "Koins" that you can use in your next in-app purchase, instead of losing it (help.kolet.com, accessed August 5, 2026).
Does Kolet offer unlimited data plans?
No. According to Holafly's review, all Kolet plans are for fixed-cap data (1 GB to 20 GB depending on the pack); there is no unlimited data option in its catalog (esim.holafly.com, accessed August 5, 2026).
How long does the free Kolet eSIM last?
Kolet's free trial is 1 GB of data, valid for 2 days from when you start using it (help.kolet.com, accessed August 5, 2026). It is not a plan intended to cover an entire trip, but to try the service before purchasing.
Does Kolet work on any phone?
No: you need an eSIM-compatible phone. Kolet reports compatibility with iOS 15.1 or higher and with recent Android models such as the Pixel line or the Galaxy S20 onwards (esim.holafly.com, accessed August 5, 2026). It is advisable to check your specific device's compatibility before purchasing any eSIM.
Does Kolet charge the same in all countries?
No. Kolet sets prices by destination and does not publish a single plan: you must check the price for the exact country within its app or in the destinations section of its website before purchasing (help.kolet.com, accessed August 5, 2026).
How is Kolet related to Air France-KLM?
Kolet has an announced integration with Air France-KLM's Flying Blue program, which provides access to Kolet data offers within the environment of these airlines (news.klm.com, accessed August 5, 2026). This explains why some travelers discover Kolet through an airline app rather than a direct search.
Conclusion
Kolet is a French travel eSIM, with serious institutional funding and a single-installation model with in-app top-ups, reporting coverage in 190 destinations and an internal credit system to avoid losing leftover data. Its clearest limitation, documented by its own help sources, is that everything passes obligatorily through its application and that it does not offer unlimited plans.
If you're looking for an international eSIM with more time to activate your plan (180 days from purchase) and 24/7 support in all languages via email and WhatsApp, without relying on a two-day trial promotion, you can check out the plans available in PuraSIM's international eSIM collection mentioned above. And if this is your first time using this technology, you should start with our definitive guide to eSIM for travel, where we explain step-by-step how to choose and use an eSIM without surprises.
