Japan has three major mobile networks — NTT Docomo, SoftBank, and KDDI/au — and choosing between them is one of the more consequential decisions a Japan traveler can make before departure. It is also one of the most underexplored, because most eSIM providers present their products as interchangeable and most travelers assume Japan’s coverage is
Japan has one of the most advanced mobile network infrastructures on the planet. Walk through the underground corridors of Shinjuku Station, ride the Shinkansen at 320 km/h between Tokyo and Osaka, or hike a mountain trail in rural Nagano — you’ll have mobile signal in places that would be dead zones in most other countries.