eSIM for Japan — Tokyo, Kyoto, Osaka, and the whole country

Japan is one of those destinations that changes the perspective of those who visit it. Between Kyoto's ancient temples, Tokyo's futuristic neighborhoods, and Osaka's gastronomic energy, the country is a constant contrast that never ceases to surprise. But to enjoy it without stress, you need one basic thing from the start: internet connection.

Unlike in many countries, in Japan you cannot buy a pre-paid SIM at any kiosk just by showing your passport. Local regulations have historically made it somewhat complicated to quickly get mobile data. This is where the eSIM becomes your best ally: you set it up from home, activate it as soon as you land, and that's it. No queues, no paperwork, no surprises.

In this guide, we explain everything you need to know to choose the best eSIM plan for Japan, how many GB are enough depending on your travel style, and how to take advantage of the country's incredible telecommunications infrastructure from the first minute.

1. Internet in Japan: what you need to know before you arrive

Japan has one of the most advanced telecommunications infrastructures on the planet. The three major operators—NTT Docomo, SoftBank, and au (KDDI)—cover practically the entire national territory with high-speed 4G LTE networks, and the deployment of 5G in major cities is advancing at an accelerated pace. In practical terms, this means you will have signal almost everywhere: from the center of Tokyo to the rural villages of Nara prefecture.

However, for a foreign traveler, accessing that connectivity has not always been easy. Until a few years ago, the most common option was to rent a pocket WiFi at the airport or buy a data SIM in specialized stores. Both options have their drawbacks: the pocket WiFi is an extra device that you must carry and return, and physical tourist SIMs usually have usage restrictions or require in-person registration.

The eSIM has completely changed this landscape. Today you can contract your data plan before leaving home, download the profile to your smartphone, and have internet working in a matter of minutes after landing at Narita or Haneda airport. It is the most convenient method, usually the most economical, and also requires no additional hardware.

Another important advantage: with an eSIM, you keep your local phone number active (in physical SIM mode) while using the data from the Japanese eSIM. This way, you can receive calls from your bank, SMS verifications, and work messages without any problem.

The speeds you can expect in major cities are excellent: between 50 and 150 Mbps download on 4G LTE under normal conditions, and peaks of several hundred Mbps in areas with 5G. Enough for high-definition streaming, fluid video calls, and instant map loading.

2. How many GB do you need for your trip to Japan?

The answer depends on your travel style, but for a 10-day trip to Japan our recommendation is clear: between 10 and 15 GB are enough for most travelers. Here's why.

Data usage in Japan tends to be more intensive than in other destinations because you rely heavily on the connection to get around. Google Maps (or Apple Maps) is practically indispensable for navigating the complex public transportation system, especially in Tokyo where subway lines overlap in multiple layers. In addition, language is a real barrier: translation apps like Google Translate with the camera activated constantly consume data when you use them to read menus or signs in Japanese.

An approximate breakdown by daily use:

• Navigation with maps: 100-200 MB per day if you have offline maps downloaded, up to 500 MB if you use online permanently.
• Social networks and messaging: 300-600 MB per day with normal use (uploading photos to Instagram, WhatsApp, etc.).
• Translation with camera: 50-150 MB per day depending on frequency of use.
• Occasional streaming: 1-2 GB per hour of HD video. If you plan to watch series on the Shinkansen, count separately.
• General searches and web browsing: 100-200 MB per day.

Adding it all up, moderate-to-high use ranges between 1 and 1.5 GB per day. For 10 days, a 10 GB plan is the recommended minimum, and 15 GB gives you comfortable leeway if you're someone who posts a lot of content or wants to watch some streaming during long train journeys.

If your trip is shorter (5-7 days) or you are a lighter data user, a 5-8 GB plan may be sufficient. The important thing is not to run out of data halfway through your trip, because in Japan free public WiFi is not as abundant as in Europe or Latin America.

3. Connectivity in Tokyo, Kyoto and Osaka

The classic Japan route—Tokyo, Kyoto, and Osaka—covers three cities completely distinct in character but equally well connected. Here’s what to expect in each.

Tokyo

The capital is a technological beast. 4G/5G coverage in Tokyo is practically ubiquitous, including on subway platforms and in tunnels. This surprises many travelers: in cities like Madrid or Mexico City, it's common to lose signal underground, but in Tokyo, the subway has coverage in almost all stations and on the trains themselves. You can browse, check maps, and receive messages while traveling on the JR Yamanote Line or any of the Tokyo Metro and Toei subway lines.

The most visited neighborhoods—Shibuya, Shinjuku, Harajuku, Akihabara, Asakusa—have excellent coverage both in open spaces and inside shopping malls and restaurants.

Kyoto

Kyoto has equally solid coverage, although as a city with more natural and temperate spaces (gardens, mountains, trails), there may be some specific spots with weaker signal. In the most popular temples like Fushimi Inari, Kinkaku-ji, or the Arashiyama Bamboo Grove, coverage is good. Where you might notice some instability is on mountain trails away from the center, but for most tourist visits, you won't have a problem.

Osaka

Osaka is Japan's third most populous city, and its coverage reflects that. Areas like Dotonbori, Namba, Shinsaibashi, and Umeda have excellent signal. Osaka's subway also has coverage in most of its stations. The city is very compact and easy to navigate, which means less data usage for maps compared to Tokyo.

Between cities, Shinkansen (bullet train) journeys deserve special mention. The Tokyo-Kyoto-Osaka route takes between 2 and 3 hours, and coverage during the journey is good in urban areas and open stretches. In some tunnels you may notice brief outages, but in general you can work, watch content, or be on a video call for a good part of the trip.

4. How to activate your eSIM for Japan step by step

Activating a PuraSim eSIM for Japan is a simple process that you can do in less than 10 minutes. Here are the detailed steps:

Step 1: Check if your phone is eSIM compatible. The vast majority of smartphones launched since 2019 support eSIM. On iPhone: go to Settings → General → About → and look for "EID Number". On Android (Samsung, Google Pixel, etc.): go to Settings → Connections → SIM Manager and look for the option to add digital SIM. If you see these options, your phone is compatible.

Step 2: Choose your plan on PuraSim. Go to our Japan plans store, select the GB and days you need, and complete the purchase. You will receive an email with a QR code.

Step 3: Install the eSIM profile. Open your phone's camera app (or the QR scan option in SIM settings) and scan the QR code you received. The profile will download in seconds. Do this before leaving home, when you still have WiFi available.

Step 4: Set the eSIM as your data source. On iOS: Settings → Cellular Data → select the Japanese eSIM as the data line. On Android: Settings → Network → SIM → mobile data → select the eSIM. Keep your local SIM as your call and SMS line.

Step 5: Activate data upon arrival in Japan. The eSIM will automatically detect local networks (Docomo, SoftBank, or au, depending on the plan). In some cases, it may take 1-2 minutes to register the first time. If you are on the Shinkansen from the airport, you can activate data during the journey without any problem.

Extra tip: Download offline maps for Tokyo, Kyoto, and Osaka in Google Maps before you leave. This way, you use much less data for navigation and only connect for real-time searches.

5. Local tips for getting the most out of your eSIM in Japan

Beyond pure connectivity, there are some things you should know to use technology intelligently during your trip to Japan.

The Tokyo subway and Shinkansen are perfect for activating your eSIM on the go. As mentioned before, Japanese public transport has enviable mobile coverage. If you arrive at Narita or Haneda airport, you can activate your eSIM during the train journey to central Tokyo. The Narita Express takes about 60 minutes, more than enough time for the eSIM to register and work perfectly.

Download these apps before you arrive: Google Maps (with offline maps), Google Translate (download the Japanese language pack for offline use), Hyperdia or Japan Transit Planner for train schedules, and IC Card (Suica or Pasmo) for public transport payment. All of them work best with a good connection.

Take care of your battery. Constantly using GPS and data on a busy day of sightseeing can drain your phone's battery. Always carry a power bank: in Japan there are vending machines for rental power banks (Smadori service), but it's better not to rely on them.

WiFi in hotels and accommodations is generally good in Japan, especially in hotel chains. You can take advantage of the night to make heavy downloads (maps, offline content) and save your mobile data for the day. Ryokans (traditional inns) also usually have WiFi, although sometimes slower.

Avoid roaming from your home operator. International roaming rates from most Latin American and Spanish operators in Japan are high. One day of roaming can cost you the same as a whole week of eSIM. If your plan includes "free roaming," read the fine print: many have very low speed limits (128 Kbps or less) that make any task beyond basic messaging useless.

Frequently asked questions

Escrito por Marc González Sáez Fundador de PuraSim y especialista en eSIM y conectividad para viajeros. Lleva años ayudando a viajar conectado por todo el mundo sin pagar de más por el roaming, y prueba personalmente las eSIM en cada destino antes de recomendarlas.