What is an eSIM and how does it help you in Japan?
An eSIM for Japan is a digital chip installed on your phone without a physical card, providing mobile data as soon as you land, with coverage from Japanese networks. You buy the plan online, install the profile with a QR code, and activate the connection upon arrival, without having to search for a carrier store at the airport.
The difference from what you probably know—a physical SIM you buy in a store—is that there's no card to insert or tray to open with a clip here. The profile is saved directly on your phone, just like a credit card saved in an app, and you activate it from Settings when you decide.
If you've never installed an eSIM and want to understand the full concept before proceeding—what happens if you change phones, how it coexists with your usual line, what you need from your current carrier—you'll find a dedicated getting started guide in the conclusion below. Here, we focus on what changes specifically when the destination is Japan.
How can I get internet in Japan if I'm traveling from Mexico, Colombia, or Argentina?
From the moment you leave your country until you arrive at Narita, Haneda, or Kansai, you actually have three distinct ways to get data, and it's good to know all three before deciding which one suits you best.
The first is international roaming from your own carrier: you activate an option from your usual line and continue using the same number in Japan. It works, but the cost varies greatly depending on the carrier and the plan you have contracted in your country, so before relying on it, it's worth checking exactly what your current plan includes and what it charges extra. If you want to compare roaming in depth against other options, there is a guide dedicated to eSIM versus roaming.
The second way is to buy a physical Japanese SIM upon arrival, which involves finding a counter at the airport or a convenience store, completing the process on the spot, and ending up with a card that you have to remember to remove before putting yours back in. The third, and the one that resolves the friction of the other two, is a data eSIM: you buy and install it before leaving home, using your usual Wi-Fi, and only activate the data when you are already in Japan. You don't depend on finding an open counter or waiting in line after a long flight.
Where to buy an eSIM for Japan?
There are, in practice, three types of sellers. The first are the Japanese carriers themselves (NTT Docomo, au, SoftBank, Rakuten Mobile), who offer their eSIM profiles through their app or website, although some of these processes are designed primarily for residents and require information that a visitor doesn't always have on hand, such as a local address.
The second are global brands with a dedicated Japan offering, such as Ubigi (from the French operator Transatel), which builds specific plans for this destination: if you're interested in seeing how that specific option works, there's a guide on Ubigi eSIM for Japan with details. The third are travel eSIM stores that cover many countries at once, including Japan, and are useful whether your trip ends there or continues to another destination in the region.
At PuraSIM, this third option is resolved through the international eSIM collection (you'll find it linked below), where you can choose the Japan plan or one that combines several countries if your itinerary crosses borders. The purchase process is the same regardless of the destination: you choose the plan, pay online, and receive the QR code by email almost immediately, with up to 180 days from purchase to install and activate it whenever you want.
What is the best eSIM in Japan?
It's the most common question, and also the one with the fewest honest single answers. There isn't one eSIM that's best for everyone: there's one that best suits your specific trip, and that depends on a handful of factors you can review before buying any plan.
There is no "best" eSIM in abstract for Japan: there is one that fits how many days you will be there, how many gigabytes you usually use, and whether your trip ends there or continues to another country.
| What to check | Why it matters | Question you should ask yourself |
|---|---|---|
| Coverage | Some plans are Japan-only, others cover several Asian countries | Does my trip end in Japan or do I continue to another destination? |
| Data amount | Using maps and browsing consumes differently than watching videos or working online | How much do I usually spend on a similar day of use? |
| Plan duration | A short plan that falls short forces you to buy again mid-trip | How many full days will I be in Japan? |
| Network type | Actual speed depends on whether the plan uses 4G, 5G, or both | Does the plan indicate which local networks it works with? |
| Support | If something goes wrong, the language and channel you can write through matters | Is there support in English and outside business hours? |
Review this list before comparing specific plans: an eSIM that seems cheap but runs out of data halfway through the trip ends up costing more time (and more stress) than one properly sized from the start.
How much does an eSIM for Japan cost?
The price of an eSIM for Japan is not a fixed number: it changes depending on how many days your trip lasts, how many gigabytes you need, and whether the plan covers only Japan or several countries in the region. That's why we're not giving you a figure here—any price you see today could change tomorrow, and what matters is that you understand what moves that number up or down before comparing.
| Factor | How it affects the price |
|---|---|
| Days of coverage | More days of active plan, higher total cost |
| Gigabytes included | More available data, higher plan price |
| Coverage (Japan-only vs. regional) | A plan covering multiple countries usually costs more than a single-destination one |
| Network speed (4G/5G) | Access to faster networks can influence plan price |
The most reliable way to compare is always the same: first define how many days and how many gigabytes you truly need (the previous section helps with that), and only then compare the price of plans that cover exactly that combination. Comparing a 5-day plan with a 15-day plan doesn't tell you anything useful about which is cheaper.
Is your phone compatible with eSIM before going to Japan?
Before buying any plan, confirm this directly on your phone: go to Settings and look for the "Add eSIM" or "Add mobile plan" option. If it appears, your phone is compatible; if not, no eSIM plan will work on that device, regardless of the destination.
Generally speaking, recent iPhones (those with Face ID instead of a home button), recent high-end Samsung Galaxy phones, and recent generation Google Pixel phones already come with eSIM factory-installed. One detail often overlooked: if your phone came with a carrier from your country, it may sometimes be region-locked to prevent adding eSIM profiles from other brands, even if the hardware is compatible. It's worth confirming with your carrier before traveling, not upon arrival in Japan.
For the most detailed list by brand and model before deciding, check this guide to eSIM-compatible phones.
How to install and activate your eSIM before flying to Japan?
The process doesn't depend on the destination, but on your phone's operating system: on iOS and Android, your phone asks you to scan a QR code (or tap a direct installation link on some models) from Settings > Mobile Data or Settings > Mobile Network.
What is advisable to adjust when the destination is a long trip, like Japan, is the timing of each step. Since you have 180 days from purchase to activate the eSIM, there's no need to wait until the day of the flight: buy the plan calmly, install the profile that same night with your home Wi-Fi—the entire process takes a couple of minutes—and leave it there, installed but inactive. Activate it only when you land, in approximately one minute from Settings. This separation between installing and activating is precisely what prevents you from relying on the often-congested Wi-Fi at Narita or Haneda airport in the first hours after a flight of more than twelve hours.
For full details, including steps by operating system and common errors when scanning the QR, we have a step-by-step guide to eSIM installation.
eSIM vs. physical SIM vs. pocket wifi in Japan
Japan is one of the few destinations where "pocket wifi" (a portable router that you rent) is still a highly promoted option, so it's worth putting it alongside the other two in the same table.
| Solution | What it entails | Main friction |
|---|---|---|
| Data eSIM | Digital profile you install before traveling and activate upon arrival | Requires a phone with native eSIM support |
| Physical Japanese SIM | Card you buy at a counter or convenience store upon arrival | On-the-spot process, cannot be prepared from home |
| Pocket wifi | Portable router you pick up and return at the airport, and carry with you | Mandatory pickup and return, its own battery that needs charging, and an extra device you must not forget or lose |
Pocket wifi has a real advantage when traveling in a group and everyone shares a single connection, because it distributes data among several devices at once. But if you're traveling alone, as a couple, or everyone with their own phone, carrying an additional router—with its cable, battery, and the hassle of returning it before your return flight—is usually more friction than it solves. To delve deeper into the comparison between eSIM and physical SIM, including what happens if you lose your phone, there's an article dedicated to that comparison.
Real-world example: 10 days in Tokyo, Kyoto, and Osaka with an eSIM
Let's consider a specific case. Someone leaves Mexico City, Bogotá, or Buenos Aires with a 10-day itinerary: four in Tokyo, three in Kyoto, and three in Osaka, traveling between cities by train. Before leaving, they buy the data plan for Japan, install it that same night using their home Wi-Fi, and leave it inactive, as seen in section 7.
Upon landing at Narita, they activate the data from Settings while walking towards immigration, without looking for a counter or waiting in line. During the trip, they use their phone mainly for maps, trains, translation, and messaging—the most common consumption pattern for this type of trip—and the coverage doesn't change between Tokyo, Kyoto, and Osaka because the plan works on Japanese 4G and 5G networks, not just one city. If the itinerary at some point extends to South Korea, the same pattern repeats with a separate plan for that destination.
The most common mistake on such a trip isn't about coverage, but about calculation: underestimating how many gigabytes are spent on constant navigation between train stations and ending up with an exhausted plan before the last day. If something similar happens to you, or any other unforeseen installation issue, there's a guide to common eSIM problems with the most frequent solutions.
Frequently asked questions
Do I need a different eSIM if I go to several cities in Japan?
No. The coverage of an eSIM plan for Japan works on national networks, not just one city, so the same plan serves you in Tokyo, Kyoto, Osaka, or any other part of the country without needing to change anything when moving between cities.
Can I install the eSIM before leaving my country?
Yes, and it's recommended. You can install the profile with your home Wi-Fi and leave it inactive until you land in Japan. You have 180 days from purchase to activate it, so there's no rush to do it on the same day of the flight.
Does the eSIM give me a Japanese phone number?
Most travel eSIMs for Japan are data-only, without a local number for calls or SMS. Your usual number still works for WhatsApp and internet calls once you have active data; what changes is the connection, not your main line.
What happens if my phone is not eSIM compatible?
Then you'll need a physical Japanese SIM or a pocket wifi router, because no eSIM plan will work on a phone without that capability, regardless of the destination. Confirm compatibility in Settings before buying any plan.
How long does it take for the eSIM to activate upon arrival in Japan?
Activation takes approximately one minute from the moment you turn it on in Settings, provided you have already installed the profile beforehand. If you install and activate everything at the same time at the airport, the complete process takes a bit longer.
Can I use my regular physical SIM at the same time as the eSIM in Japan?
Yes, on a phone with native eSIM support, the physical SIM and the eSIM work simultaneously in dual mode. You can leave your usual line active for WhatsApp calls and use the Japanese eSIM only for data.
What should I do if I have a problem with the eSIM during my trip to Japan?
PuraSIM support is available 24/7 in all languages via email and WhatsApp, so you don't depend on an office schedule in another time zone or on finding a physical store of a Japanese operator.
Does the same eSIM work if I go to another country after Japan?
It depends on the plan: some cover only Japan, and others include several countries in the region in the same profile. If your itinerary crosses borders, it's worth checking from the beginning whether a regional plan is better for you instead of buying a new one for each destination.
Conclusion: what to do before your trip to Japan
If you've never used an eSIM, the order that simplifies things most is this: confirm your phone is compatible (section 6), define how many days and gigabytes you need according to your itinerary (section 4), buy the plan calmly and not at the last minute, install it with your home Wi-Fi, and activate it only upon landing in Japan (section 7).
If this is your first time with this process, start with the getting started guide on what an eSIM is and, once your itinerary is clear, choose your plan from the international eSIM collection, where you can compare the Japan plan against regional options if your trip continues to another country. With up to 180 days from purchase to activate and an activation of approximately one minute once you land, there's no reason to leave it until the last day before your flight.
