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Internet in Japan: how to get online and get around

In Japan, your phone’s data is mostly about finding your way: train connections, platforms, walking routes and translation. Having data from the moment you land makes the trip much easier. This guide compares the options and covers network coverage, public Wi-Fi, useful apps and how to set up an eSIM.

Ways to get online in Japan

There are four options: roaming with your usual provider, a local SIM card, a rented pocket Wi-Fi router and a data eSIM. Our guide to eSIM, local SIM or roaming compares the first three in detail.

Roaming

Japan lies far outside the European Union and many of the zones included in mobile plans, so roaming there can be expensive. If you intend to use it, check the rates and allowances with your provider before you leave.

Local SIM and pocket Wi-Fi

Data SIM cards for visitors are available, as are pocket Wi-Fi routers to rent. A router can connect several devices, but you have to collect it, charge it every day, carry it with you and return it at the end of your trip. A physical SIM, for its part, means removing your usual SIM if your phone does not support dual SIM.

A data eSIM

The Alizeoo eSIM provides mobile data with no Japanese number and no standard calls; WhatsApp, FaceTime and other internet calling apps work. You install it before you go, there is nothing to collect or return, and your usual SIM stays in place. If you also want to connect a tablet or laptop, check that tethering is allowed: this is shown on the plan page. Your phone must support eSIM and be unlocked: check with our compatibility guide.

Networks and coverage

The main Japanese mobile operators are NTT Docomo, KDDI (under the au brand), SoftBank and Rakuten Mobile. The country has both 4G and 5G. Alizeoo plans for Japan run on partner operators, currently NTT Docomo, SoftBank and KDDI; the exact networks for each plan are listed on its page, as they can change. 5G depends on the plan, the partner operator and your phone: without it, you connect over 4G.

Coverage is generally good in the cities and at stations. It can vary:

  • in some rail and road tunnels;
  • in the mountains and on hiking trails;
  • on some outlying islands and in sparsely populated rural areas.

If the eSIM will not connect where there is network coverage, follow our guide my eSIM has no signal.

Public Wi-Fi in Japan

Free Wi-Fi is available at airports, many stations, hotels and some shops, often after a sign-up or a welcome page. It is fine at the hotel but not always there while you are travelling. As anywhere, avoid entering card details or passwords on it and keep your mobile data for anything sensitive.

Useful apps

  • Map and transport apps, which show connections, platforms and times: this is the main use of data in Japan.
  • Rechargeable transport cards such as Suica, which can be added to a mobile wallet on compatible phones.
  • LINE, a messaging app widely used in Japan, and WhatsApp for keeping in touch with people back home.
  • A translation app, handy for menus and signs; download Japanese for offline use if the app allows it.

Some restaurants and services ask for a phone number to make a booking. The eSIM does not provide one, so keep your usual number reachable or book through an app.

Installing and activating your eSIM

Install the eSIM at home over Wi-Fi before you leave, and you will be online as soon as you land. The menus are explained in our iPhone and Android guides.

  1. Choose a Japan plan: the QR code and installation link arrive by email and in your account.
  2. Before you leave, on Wi-Fi: scan the QR code or tap ‘Install in one tap’, then name the line Alizeoo.
  3. When you land: select Alizeoo for mobile data and turn on data roaming for that line.
  4. Turn off data and roaming on your usual SIM to avoid charges from your provider.

The plan’s validity usually starts the first time you connect in Japan; the plan page gives the details. To keep your usual number active alongside it, see our dual SIM guide.

A Japan plan covers Japan only. If you are travelling on to South Korea or elsewhere, plan your multi-country trip and check the list of countries on each plan page.

How much data will you need?

Maps, transport navigation and messaging use little data, but you rely on them all day long. Video, video calls and posting photos and clips push usage up. For an estimate based on how you use your phone and the length of your stay, use the estimator on our Japan eSIM page.

Before you go

  • Make sure your phone supports eSIM and is unlocked.
  • Install the eSIM before you leave and do not delete it afterwards: it usually cannot be reinstalled with the same QR code.
  • Each eSIM installs on one device only, so every traveller needs their own.
  • Download offline maps and your bookings before trips into the mountains.

To compare durations and allowances, see the plans for Japan. Prices include tax and are shown in US dollars.

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