Internet in Japan for tourists: the options, and which one fits your trip

Why a European plan gets expensive in Japan

The EU's Your Europe portal is clear about the limits of free roaming. It covers EU countries, the EEA members Iceland, Liechtenstein and Norway, and also Moldova and Ukraine. Other countries are not part of the regime, and the portal warns that roaming outside the EU and EEA can be expensive. Japan is one of those other countries, so your operator charges whatever its own rates for Japan are, unless you buy a specific add-on from it.

There is a safety net, though it is not a plan. Malta's communications regulator explains that the EU data cut-off, set close to 50 euros a month before taxes unless you choose another limit, also applies when roaming outside the roam-like-at-home zone, with a warning at 80 % of it. Where the operator cannot apply it in a given country, it has to tell you in the message you get on arrival. Either way, the simplest protection is to switch off roaming on your home line before landing; the steps are in the guide on turning off roaming on your home line.

The four ways to get online, side by side

• Travel eSIM: a data plan installed in your own phone from a QR code, ideally at home on Wi-Fi. It needs a phone that takes eSIMs and is not locked to a carrier, and your usual SIM stays in place.
• Pocket Wi-Fi: a small battery-powered router. Japan's national tourism organisation (JNTO) says rental kiosks are at all major airports, and that you can also book online and have the device delivered to your hotel.
• Prepaid SIM: JNTO says you can rent or buy one, with data plans at major airports and SIM cards at big electronics stores in the cities. Your phone must be unlocked, and the new card replaces your home SIM in its slot.
• Free Wi-Fi: available in airports, many hotels and some shops, but you have to find it and sign up, which makes it a backup rather than a way to navigate a city.

To check an eSIM first: Apple says you need an iPhone XS or later that is not locked to a carrier, which you can see in Settings, General, About, next to Carrier Lock, where it should read No SIM Restrictions. Google says a Pixel 3a or later can hold a physical SIM and an eSIM at once. The list of compatible phones covers other models. A pocket Wi-Fi makes more sense when one device has to connect several people or laptops; the trade-offs are in eSIM or pocket Wi-Fi.

Free Wi-Fi: where it really is

JNTO lists free Wi-Fi inside the terminals of Narita, Haneda's international terminal, Kansai, New Chitose, Centrair and Fukuoka, and notes that the way to connect differs from one airport to the next. Most large hotels in the cities offer Wi-Fi to guests, while traditional ryokan and small minshuku in mountain or rural areas may not, so it is worth asking when you book. Coffee chains, fast food restaurants and convenience stores sometimes have their own networks, but you have to register and JNTO describes the signal as patchy and slow.

To avoid signing up network by network, NTT Broadband Platform offers Japan Wi-Fi auto-connect, a free app for iPhone and Android. You register once and it connects you to the free spots it supports as you reach them; its OpenRoaming support needs iOS 15 or Android 11 or later. Even JNTO, which promotes these networks, says hotspots are common in big cities but recommends a rented connection for guaranteed access, especially in remote areas.

On the Shinkansen and at the stations

Central Japan Railway runs Shinkansen Free Wi-Fi, which it says is available in all trains of the Tokaido, Sanyo and Kyushu Shinkansen. You pick Shinkansen_Free_Wi-Fi from the list of networks and register an email address or log in with a social media account; you can use it as often as you like, but it asks you to log in again every 30 minutes. At ground level, the company's JR-Central Wi-Fi covers every Tokaido Shinkansen station near the ticket gates or waiting rooms, and some platforms at Tokyo, Shinagawa, Shin-Yokohama, Odawara, Nagoya, Kyoto and Shin-Osaka.

That page only covers JR Central's own trains and stations, so do not assume the same on other lines. With mobile data on your phone you are not depending on any of it: a re-login every half hour matters little if the train network is only your backup. For the city part of the trip, the guides to mobile data in Tokyo and mobile data in Osaka go through airports, stations and day trips.

The apps that need a connection in Japan

Trains are where data matters most. Google's own help page says that, offline, transit, bicycling and walking directions are unavailable; downloaded maps only give driving directions. So the downloaded map is a backup, and planning a route with changes between rail companies needs a live connection. A translator works partly offline: Google says camera translation in the Translate app keeps working for languages you have downloaded, so download Japanese at home and keep data for conversation and anything else.

Paying for transport can also live on the phone. JR East's Welcome Suica Mobile, for iPhone with iOS 17.2 or later, creates a Suica in the app with a secret keyword and no membership registration, and you top it up with a card in Apple Pay. If someone you meet in Japan asks you to add them on LINE, LY Corporation's messaging app, it works over data like any other. WhatsApp keeps your usual number on a data eSIM, as the guide on keeping your WhatsApp number explains.

How much data per day: measure it on your own phone

No official body publishes a figure per day for tourists, and any number depends on how you use the phone. Your phone can tell you. On an iPhone, Apple's guide puts it under Settings, Cellular: scroll to the list of apps and tap Show All, and the cellular data used appears under each one, with Reset Statistics at the bottom. Reset it, spend an ordinary day at home with Wi-Fi off, using maps, messages and photos as you would on the trip, and read the total.

Multiply that by the days in Japan and add a margin for what you do more of when travelling: route searches, uploading photos and video on long train rides. Sharing data with a companion through the hotspot adds their use to yours. If you want to save, Apple's Low Data Mode, under Settings, Cellular, Cellular Data Options, Data Mode, pauses automatic updates and background tasks when you are not on Wi-Fi. The data calculator and the guide on how much data you need turn your habits into a number.

Fixed data or unlimited: the two kinds of Japan eSIM

Snoozim sells two kinds of plan for Japan. The fixed-data plans come in 3, 5, 10 and 20 GB; the 3 GB one lasts 15 days and the others 30. They connect to NTT docomo, KDDI/au, SoftBank and Rakuten Mobile, and the phone moves to whichever has the best signal where you are. They start counting at the first connection in Japan, you can top them up without reinstalling, and they carry data only, with no Japanese phone number.

The unlimited plans run on KDDI (au) 5G with a Japanese IP address, for 7, 10 or 15 days counted by calendar day in Japan time from the first connection. They come with conditions worth reading first: they cannot be topped up, so choose a length that covers the whole stay; they install only once, so if you delete the eSIM it cannot be installed again; once delivered they cannot be refunded; and the network does not report usage, so you will not see how much you have used. For that plan, the Japan page also says to keep Data Roaming off on the eSIM for the best connection. What unlimited usually means on travel plans is explained in what unlimited data means on a travel plan.