Japan 50GB 30 days
NTT docomo / Rakuten Mobile / KDDI/au
Exits in Hong Kong · NTT docomo / Rakuten Mobile / KDDI/au
- データ
- 50GB
- 有効期間
- 30 days
- テザリング
- 可
- 通信方式
- 3G / 4G / 5G
- 5G対応
- テザリング
- 追加チャージ対応
Validity starts on first connection at the destination
A country long enough north to south to hold two seasons on the same day — choosing a month is really choosing which part of it to be in.
If you must pick one window without a specific activity in mind, October into early November gives the most usable weather per day on the ground: little rain, comfortable temperatures, and the country not yet in end-of-year congestion. If snow or blossom is the point, choose by the phenomenon instead and accept the crowds that come with it.

Japan has four distinct seasons and people genuinely plan around them. Spring and autumn are the two most comfortable stretches and, for the same reason, the busiest. Summer is hot and humid in the big cities but it is the only time the high mountains and Hokkaido are at their best. Winter splits the country between a snow-heavy side and a dry, sunny one. Picking a month therefore has to be paired with picking a region rather than decided on its own.
If you must pick one window without a specific activity in mind, October into early November gives the most usable weather per day on the ground: little rain, comfortable temperatures, and the country not yet in end-of-year congestion. If snow or blossom is the point, choose by the phenomenon instead and accept the crowds that come with it.
Golden Week in early May, the mid-August holiday and new-year week are the three stretches when the whole country travels at once: bullet-train seats sell out ahead and room rates climb visibly. If you cannot avoid them, reserve seats in advance rather than counting on finding one.
Coverage in cities and along the main rail corridors is strong all year. What changes with the season is where you end up: ski areas in winter and mountain trails in summer are where signal genuinely thins. Download maps and timetables before leaving the city, every time.
NTT docomo / Rakuten Mobile / KDDI/au
Exits in Hong Kong · NTT docomo / Rakuten Mobile / KDDI/au
Validity starts on first connection at the destination
NTT docomo
Exits in Japan · NTT docomo
Validity starts on first connection at the destination
NTT docomo / Rakuten Mobile / KDDI/au
Exits in Hong Kong · NTT docomo / Rakuten Mobile / KDDI/au
Validity starts on first connection at the destination
KDDI/au
Exits in Singapore · KDDI/au
Validity starts on first connection at the destination
NTT docomo
Exits in Japan · NTT docomo
Validity starts on first connection at the destination
NTT docomo / Rakuten Mobile / KDDI/au
Exits in Hong Kong · NTT docomo / Rakuten Mobile / KDDI/au
Validity starts on first connection at the destination
Within a window, not to the day. The date shifts by several days year to year depending on the winter before it. If the trip really hangs on the bloom, allow a wide window and keep a later-blooming city as a backup.
Yes if your plans are mostly urban. It rarely rains all day, and museums, restaurants and shopping districts are unaffected. Room rates in this window sit noticeably below high season.
Sharply but briefly. Flights and some rail lines stop pre-emptively for safety and generally resume within a day or two. Having working data matters most in exactly these days, because the operators announce changes in their own apps before anywhere else.