eSIM for Japan
Updated 2026-08-22
Networks and coverage
NTT Docomo, SoftBank and KDDI au run the networks, and all three have coverage few countries match. 4G and 5G reach smaller towns and the metro.
The Shinkansen has a connection nearly the whole way, including through many tunnels. It thins out only in the Japanese Alps and on smaller southern islands.
How much data do you need?
10 GB for two weeks is a good starting point. Japan is a country where you use the phone more than expected: train times, translating menus, and navigating stations that are cities in themselves.
Using camera translation continuously, or tethering a camera, moves faster. 20 GB leaves margin.
Practicalities on arrival
Activate the line at Narita, Haneda or Kansai and turn data off on your Swedish subscription. Japanese roaming from Sweden is among the more expensive.
Download an offline map of the Tokyo metro. The stations are large enough to lose your bearings in, and down there only your own connection matters.
Common questions
- Does it work on the Shinkansen?
- Yes, coverage along the high-speed lines is very good and holds through most tunnels.
- When does validity start counting?
- When the eSIM first connects to a network at your destination, not when you buy or install it. You can prepare well in advance without losing days.
- Can I make calls with the eSIM?
- No, it is data only. Call over WhatsApp, Messenger or FaceTime, or keep your Swedish number active for ordinary calls.