WhatsApp in Japan: how to use it without fees?

Your friends and family are on WhatsApp, after all. During your trip to Japan, it is the simplest way to stay in touch without changing your habits: same conversations, same groups, same number.

There is also a cost reason. With your regular plan, a call made or received from Japan is charged per minute by your operator. On WhatsApp, the call goes through the internet: it is free between two accounts and uses only a little data.

Depending on your operator, an incoming call in Japan may be charged per minute. The same call on WhatsApp uses at most 1 MB per minute, which costs only a few cents with an eSIM.

WhatsApp is also very handy when you travel in a group: a group chat to plan your days, live location to find each other in the crowds of Shibuya or at a Shinkansen station, and your tickets, reservations, and photos shared in one place.

How it works

WhatsApp in Japan works just like anywhere else in the world: the app sends your messages and calls via the internet (known as VoIP), rather than through the traditional phone network. Whether you are in Tokyo, Osaka, or a village in the Japanese Alps, as long as your phone has an internet connection, WhatsApp works.

In practical terms, once you are there, you can:

• send written messages and voice messages to your family and friends back home;
• make a voice call or a video call to any WhatsApp user, regardless of their country;
• share photos, videos, your live location, and documents;
• join or create groups, practical for organizing a trip with several people.

Messages remain end-to-end encrypted, just like at home: the app's privacy policy does not change depending on the country you are in. One limitation to keep in mind: WhatsApp only calls other WhatsApp accounts. To reach a landline or a hotel that doesn't have the app, you will need a regular phone line.

As for cost, the official WhatsApp FAQ points out that WhatsApp uses the same connection as your browser or your emails. The app is free, but if you use it while roaming, your operator may charge you for the data used. That is the whole issue on a trip to Japan.

Local popularity

In the land of the rising sun, WhatsApp remains an app for tourists and expats. People in Japan overwhelmingly prefer LINE: according to LY Corporation, the company that operates it, LINE passed 100 million monthly active users in Japan at the end of 2025.

Why don't Japanese people use WhatsApp? It's a matter of communication culture. LINE established itself very early, shortly after its launch in 2011, and it does much more than just messaging: calls, stickers, news, social networks, and official accounts used by businesses, restaurants, and hotels to communicate with their customers. When everyone around you and all your daily services are on LINE, there's little point in switching apps.

For you, nothing changes with your family and friends back home: they are on WhatsApp, and you stay on WhatsApp. To chat with people in Japan, however, plan on using LINE.

The indispensable alternative

The alternative to WhatsApp in Japan is therefore LINE. Downloading LINE takes a minute: install it from the App Store or Google Play before you leave and create your account with your usual number, as long as you can still receive verification texts without trouble.

How do I give my number to someone in Japan? In practice, people almost never swap phone numbers in Japan: they add each other on LINE. In the app, open the add friends menu, show your QR code and let the other person scan it, or search for their LINE ID. This is the reflex to have with a ryokan host, a tour companion, or someone you meet while traveling. WhatsApp also offers a contact QR code, in the settings next to your name: useful with other international travelers.

Other messaging alternatives also work in Japan, always using data:

Connection

To use WhatsApp in Japan, you simply need internet. You have two main ways to connect:

• Wi-Fi: free in airports, many train stations, hotels, and konbinis. Perfect for an evening call at the hotel, much less reliable on the street. Everything is detailed in our article on free wifi in Japan.
• Mobile data (mobile internet): with your usual roaming plan, a Japanese SIM card, or an eSIM. This is what allows you to reply to a message in the subway, share your live location, or make a call in the middle of the street, with Google Maps open at the same time.

With mobile data, you can also turn on hotspot sharing to connect a tablet or a travel companion's laptop. On a public Wi-Fi network, avoid opening your banking apps: WhatsApp stays encrypted, but an open network is never a trusted connection.

Keeping your number

It is the question everyone asks: does your WhatsApp number change in Japan? No. Your account is linked to the number you verified when you registered, not to the SIM card that gives you internet. Whether you choose a SIM or an eSIM in Japan, or simply stay on Wi-Fi, your contacts will always see your usual number, and your conversations stay intact.

Does WhatsApp work with an eSIM? Yes, and it is actually the most convenient setup. Most recent smartphones are dual SIM: your primary SIM (your home SIM) stays installed to receive your texts and calls, and the data-only eSIM provides internet. How it works is explained in detail in our article on eSIMs and phone numbers.

Three precautions to keep your account working without trouble:

1. Verify your account before you leave. If you change phones or reinstall WhatsApp, the app sends you a code by text. A data-only eSIM cannot receive texts: do this at home.
2. Do not remove your home SIM. Keep it active (but with data roaming off) so you can receive a verification code if needed.
3. Enable two-step verification in your WhatsApp settings: a PIN code protects your account if someone tries to activate it on another phone.

You have several ways to get internet in Japan for using WhatsApp. Here are the best options, from the simplest to the most restrictive, in our view.

The travel eSIM

The travel eSIM is a virtual SIM card that you install from your phone, by scanning a QR code or via an app, even before you leave. Once in Japan, it connects to the local network and WhatsApp works as soon as you step off the plane.

Its advantages for WhatsApp:

• you keep your usual WhatsApp number and your home SIM;
• you buy it online: no store visit, no passport to show at the counter, no physical SIM to handle;
• a price known in advance, with no nasty surprises on your bill when you get back.

At voilà eSIM, the eSIM for Japan runs on the NTT Docomo 5G network. Plans start at $1.40 for 1 GB over 7 days, with 5 GB at €5.50, 10 GB at $9.60, and 20 GB at $16.80 over 30 days. voilà eSIM means excellent value for money, an eSIM that is easy to install with an app that is easy to use, and human customer support available 24/7. Hotspot sharing is included, no apps are blocked, and you get a refund if something goes wrong. The calculator below shows the plan that fits your stay.

How it works in video:

The Japanese SIM card

You can also buy a SIM card on arrival: at Narita, Haneda, or Kansai airports, or in large electronics stores like Bic Camera and Yodobashi Camera. It costs between €24 and €55 depending on the duration, and make sure to bring your passport, as required by Japanese regulations.

A local SIM card has a drawback for WhatsApp: if your phone only has one physical slot, it takes the place of your home SIM, and you will no longer receive your texts, including verification codes. Your WhatsApp account, however, remains tied to your number. Prices and points of sale are compared in our article on the SIM card in Japan.

Your operator's roaming plan

Roaming is the simplest solution on paper: you change nothing. But Japan is rarely included in plans, and data abroad can be very expensive without an option.

Depending on your operator, data used outside your plan may be charged per megabyte, and just a few photos sent on WhatsApp can be enough to run up your bill. Travel passes limit the damage, but they generally still cost several times more than an eSIM.

Before you leave, check what your plan includes in Japan: it's the subject of our article on roaming in Japan.

Pocket wifi and public Wi-Fi

A pocket wifi is a small portable router that shares a 4G or 5G connection with multiple devices. It is rented for between €33 and €67 per week, must be recharged every evening, and returned at the end of your stay. It makes sense for a group, but much less so for a solo traveler: you can compare offers in our article on pocket wifi in Japan.

Public Wi-Fi is free and fine for an evening call. It doesn't replace a real connection when you need to send your location or make a call while on the move.

The figures published by several eSIM providers show similar orders of magnitude. Messages weigh almost nothing, while video calls weigh much more:

In short, one hour of video calling uses 180 to 420 MB, whereas one hour of voice calling does not exceed 60 MB. In HD, video calls can climb to 12 to 20 MB per minute, or up to 1.2 GB per hour, according to the details published by the eSIMrat comparator. To reduce your data usage, turn on the option that uses less data for calls in WhatsApp's storage and data settings, and turn off automatic media downloads over mobile data.

For chats (messages, photos, voice messages), the calculator below uses the range from our data usage simulator: 10 to 50 MB per hour of messaging. It adds your calls and then, if you wish, the rest of your usage based on the same profiles as the simulator (about 0.5 GB per day for light usage). You get the total data for your trip and the plan that covers it.

If you don't have the WhatsApp app yet, install it at home, not at the airport in Tokyo:

1. Download WhatsApp on the App Store (iPhone) or Google Play (Android).
2. Enter your phone number and the verification code you receive by text.
3. Choose your name and your profile photo.
4. Allow access to your contacts, microphone, and camera for calls.
5. Turn on a backup of your chats (iCloud or Google Drive) before leaving.

To make international calls, check that your contacts are saved in international format, including their country code (for example +81 for Japan). Then, open the Calls tab, choose your contact, and tap the phone or camera icon. Calls between two WhatsApp accounts are free; only data counts. To ensure good call quality, use a stable 4G or 5G connection or your hotel's Wi-Fi.

Don't forget to install your eSIM before you leave: it activates the first time you connect after you arrive.

Are your messages stuck with a little clock icon, or does WhatsApp show "Connecting"? The problem almost always comes from the connection, rarely from the application. Check in this order, then tap retry:

1. Mobile data is enabled, and it is your eSIM line that is selected for data in your phone settings.
2. Data roaming is turned on for the eSIM line (it is required for a travel eSIM) and turned off for your home SIM to avoid charges.
3. Airplane mode: turn it on for ten seconds, then turn it off, or restart your phone to force the connection to the network.
4. Wi-Fi: on a public network, open your browser and complete the login page, otherwise the internet won't work.
5. VPN: turn it off if it slows down or blocks your connection.
6. The app: update WhatsApp and check that there is enough storage space left on your phone.

If nothing works, contact your connection provider's support. At voilà eSIM, a real person answers at any hour, even in the middle of the night in Kyoto.