SIM, eSIM and wifi in Tokyo

Three options, one honest answer

For almost everyone with a phone made after 2019, an eSIM is the right call. You buy it online before you fly, scan a QR code, and data works the moment you land. No shop, no plastic, no return. A physical SIM makes sense if your phone cannot take an eSIM or is locked to a carrier that refuses them. Pocket wifi makes sense for groups of three or more sharing one connection, or for people carrying a laptop who need lots of data.

Whatever you choose, check two things before leaving home: that your phone is carrier-unlocked, and that it supports eSIM (Settings, General, About on iPhone; Settings, Network, SIMs on Android). All three Japanese networks, docomo, au and SoftBank, cover every corner of Tokyo including the subway, so the operator behind your plan barely matters.

eSIM

Ubigi, Airalo, Saily, Nomad and the Japan-based Mobal and Sakura Mobile all sell Japan eSIMs. Expect around ¥1,500 to ¥2,500 for 10 GB over two weeks, ¥3,000 to ¥4,500 for 20 to 30 GB, and ¥5,000 to ¥7,000 for a month of unlimited data. Ten gigabytes is plenty for maps, messaging and photos; streaming and video calls eat it fast.

Install the eSIM at home over wifi, label it, and leave it switched off. On landing: turn on the Japan eSIM, enable data roaming on that line only, and set it as your data line. Keep your home SIM active for calls and SMS codes, with its data roaming off, or you will pay roaming rates.

Data-only eSIMs give no Japanese phone number. That is fine for nearly everything, but some restaurant reservation sites and ticket apps want one; use your hotel’s number, or pick a provider like Mobal whose plans include a voice line.

Physical SIM and pocket wifi

Vending machines in the arrivals halls at Narita and Haneda sell prepaid data SIMs from around ¥3,000 for 7 to 15 days. In the city, Bic Camera and Yodobashi Camera have SIM counters with English-speaking staff, and some konbini sell them too. Bring a SIM tool or a paperclip, and photograph your home SIM before you take it out.

Pocket wifi (Japan Wireless, Ninja Wifi, Sakura Mobile, Global Advanced) runs around ¥700 to ¥1,000 per day for unlimited or near-unlimited data. Book online, collect it at the airport counter or have it sent to your hotel, and drop it in the prepaid envelope at any postbox before you leave. The router adds a device to charge every night, and if you split up for the day only one person has internet.

Free wifi: the reality

Tokyo has lots of free wifi and very little good free wifi. Stations, 7-Eleven, Lawson, FamilyMart, Starbucks, most department stores and the airports all offer it, usually behind a login page that times out after an hour. Metro wifi is in stations but not between them. The Japan Wi-Fi auto-connect app from NTT Broadband Platform reduces the login dance, and hotel wifi is reliable. Treat free wifi as a bonus for big downloads, not as your plan.

Google Maps offline areas, a translation app with Japanese downloaded, and your airline and hotel apps are worth installing before you leave, in case the first hour goes wrong.