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 culinary energy, the country is a constant contrast that never ceases to amaze. But to enjoy it stress-free, you need one basic thing from the very beginning: an internet connection.
Unlike many countries, in Japan you cannot buy a prepaid SIM card at any kiosk just by showing your passport. Local regulations have historically made it somewhat complicated to get mobile data quickly. This is where an eSIM becomes your best ally: you configure it from home, activate it as soon as you land, and you're ready to go. 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 very 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 virtually the entire national territory with high-speed 4G LTE networks, and 5G deployment 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 towns 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 card at specialized stores. Both options have their drawbacks: pocket WiFi is an extra device you have to carry and return, and physical tourist SIM cards usually have usage restrictions or require in-person registration.
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 it also does not require any 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.
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 is sufficient for most travelers. Here's why.
Data usage in Japan tends to be more intensive than in other destinations because you rely heavily on connectivity 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. Furthermore, the language is a real barrier: translation apps like Google Translate with the camera activated consume data constantly when you use them to read menus or signs in Japanese.
An approximate breakdown by daily use:
- Map navigation: 100-200 MB per day if you have offline maps downloaded, up to 500 MB if you use online permanently.
- Social media and messaging: 300-600 MB per day with normal use (uploading photos to Instagram, WhatsApp, etc.).
- Camera translation: 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 everything up, moderate-to-high usage 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 margin if you're someone who posts a lot of content or wants to do some streaming during long train journeys.
If your trip is shorter (5-7 days) or you're a lighter data user, a 5-8 GB plan might be sufficient. The important thing is not to run out of data halfway through your trip, because free public WiFi is not as abundant in Japan as it is in Europe or Latin America.
3. Connectivity in Tokyo, Kyoto, and Osaka
The classic Japan route — Tokyo, Kyoto, and Osaka — covers three completely distinct cities in character but equally well-connected. Here's what to expect in each.
Tokyo
The capital is a technological powerhouse. 4G/5G coverage in Tokyo is virtually ubiquitous, including on subway platforms and tunnels. This is something that 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 centers 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 signals. In the most crowded 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 the third most populous city in Japan, 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-air sections. In some tunnels, you may notice brief cuts, 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 under 10 minutes. Here are the detailed steps:
Step 1: Check that 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 a 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 → Mobile 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 when you arrive 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 of 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 to make the most of your eSIM in Japan
Beyond pure connectivity, there are a few things worth knowing to use technology smartly during your trip to Japan.
The Tokyo subway and Shinkansen are perfect for activating your eSIM on the go. As mentioned earlier, 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 an IC Card app (Suica or Pasmo) for public transport payment. All of these work better with a good connection.
Mind your battery. Constant GPS and data usage 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 accommodation 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 carrier. International roaming rates from most Latin American and Spanish carriers in Japan are high. A day of roaming can cost you the same as an entire week of eSIM. If your plan includes "free roaming," read the fine print: many have very low speed limits (128 Kbps or less) that render any task beyond basic messaging useless.
Frequently Asked Questions
Do I need an eSIM to travel to Japan?
It's not mandatory, but it's the most convenient and economical option for most travelers. With an eSIM, you avoid buying physical SIM cards at the airport, which are usually more expensive and sometimes require passport registration. Plus, you can activate it from home before you leave.
How many GB do I need for 10 days in Japan?
For a typical 10-day trip visiting Tokyo, Kyoto, and Osaka, we recommend between 10 and 15 GB. This covers constant navigation with Google Maps, use of translation apps, social media, and some streaming on Shinkansen journeys. If you are a light user, 8 GB may be enough; if you plan a lot of streaming, go up to 15 GB.
Does the eSIM work on the Shinkansen and Tokyo subway?
Yes. Japanese networks (Docomo, SoftBank, au) have coverage in most Tokyo subway tunnels and inside the Shinkansen. You can activate and use your eSIM during the train journey without problems, even from the airport to the city center.
When should I activate my eSIM for Japan?
Install the eSIM profile before leaving home while you have WiFi available, but activate mobile data when you land in Japan. If you arrive at Narita or Haneda airport, you can activate it during the train journey to the city. There's no need to rush.
Is my phone compatible with eSIM for Japan?
Most smartphones launched since 2019 are compatible: iPhone XS and later, Samsung Galaxy S20 and later, Google Pixel 3 and later, and many Huawei, OnePlus, and Xiaomi models. Check your phone's settings to see if the "Digital SIM" or "eSIM" option appears. You can also check the list of compatible devices on our help page.
Activate your eSIM before you leave and arrive connected from the very first moment. No queues, no paperwork, no surprises.
View eSIM plans →
