Staying Connected in Japan: eSIM, SIM Cards, and Pocket Wi-Fi

You will use your phone constantly in Japan: maps, train apps, translation, restaurant photos, and topping up your transit card. Free Wi-Fi exists but is patchy and requires sign-ups. Get mobile data sorted before you land.

1. Your three options

For most people the answer in 2026 is an eSIM. It is cheaper than pocket Wi-Fi, there is nothing to return, and you are online the moment the plane lands.

2. Before buying an eSIM

• Check your phone supports eSIM. iPhone XS and later, Google Pixel 3 and later, and most Samsung flagships from the S20 on. Many mid-range Android phones do not.
• Check your phone is unlocked. A phone still locked to your home carrier will not accept another network's eSIM.
• Keep your home SIM active but with data roaming off, so you can still receive verification SMS from your bank.

3. How to set it up

1. Buy the eSIM online while still at home. You will receive a QR code by email or in the provider's app.
2. On your phone, go to the cellular settings, add an eSIM, and scan the code. Do this on Wi-Fi at home — it needs an internet connection.
3. Label it "Japan" and set it as your data line, leaving your home number as the primary line for calls and texts.
4. Leave it switched off until you land, then turn it on. Most plans start counting from first connection.

4. How much data do you need

A typical tourist using maps, search, messaging, social media, and some photo uploads uses 1–2 GB per day. Video streaming and tethering a laptop use much more. For a two-week trip, 10–20 GB is comfortable; unlimited plans exist if you would rather not think about it.

5. Networks

All tourist SIMs and eSIMs run on one of Japan's three networks — NTT Docomo, KDDI (au), or SoftBank. Coverage from all three is excellent in cities and along train lines, including inside subways. Docomo has the widest rural coverage, which matters if you are heading to mountains or remote coastlines.

6. Free Wi-Fi

Available at airports, most hotels, many cafes, convenience stores, and major stations, usually after a sign-up page. It is fine as a backup but not as your only connection: it drops out between locations, which is exactly when you need the map.

7. Calls

Most tourist data plans have no Japanese phone number. That is rarely a problem: restaurants and hotels can be contacted through booking apps, and messaging apps handle everything else. If you need to make local calls (some ryokan only take bookings by phone), choose a plan that includes a number, or use your home number on roaming for the occasional call.

8. Useful apps to install before you go

• Google Maps — works well for trains, including platform numbers and fares.
• Google Translate — download Japanese for offline use; the camera mode handles menus and signs.
• Welcome Suica Mobile or Apple Wallet (iPhone) — for your transit card.
• Japan Official Travel App (JNTO) — disaster alerts and transit status in English.

Quick checklist