Japan eSIM
Japan eSIM choices for a rail trip or a longer stay
Japan's fixed-data range includes 3GB for 15 days and 5GB, 10GB or 20GB for 30 days. For a shorter visit without a volume limit, there are Japan Unlimited options lasting 3, 5, 7 or 10 days, each with a 5Mbps cap.
Choose the package, then check its network
The fixed 3GB/15-day and 5–20GB/30-day packages list NTT docomo. Other Japan options list SoftBank. Those details belong to the individual plans; they do not establish which network every Japan Unlimited or regional package uses.
Neither operator name proves uninterrupted service along a rail route or at a mountain accommodation. Keep an offline copy of your hotel details and the next transfer if your itinerary depends on having directions available at all times.
Which allowance fits your itinerary?
For a two-week visit with Wi-Fi at your accommodation, 3GB/15 days gives you a total pool to budget across the trip. A longer stay can use the 30-day fixed choices; downloads and video will draw from that same total.
Japan Unlimited is a different arrangement: no hidden volume quota, with a 5Mbps speed cap throughout the chosen validity. Network conditions can still make the actual speed lower. Compare the available durations in the Japan selection rather than assuming a longer package matches every shorter trip.
Check the country list for onward travel
The Japan-only Unlimited option covers Japan. The Asia-Pacific Unlimited selection also covers Australia, Indonesia, Cambodia, South Korea, Macao, Malaysia, New Zealand, Singapore, Thailand, Taiwan and Vietnam, as well as Japan. That 12-destination package can suit an itinerary with several stops; a Japan-only purchase does not gain that coverage automatically.
Prepare your train journeys
Japan National Tourism Organization points travellers to NAVITIME and Japan Transit Planner for route and fare searches. Before the flight, save the destination station and accommodation address, then check your onward route while you have a connection. For account-based services, confirm any phone-verification requirements separately; mobile data is not a promise of a Japanese SMS number.