Japan has three major mobile networks — NTT Docomo, SoftBank, and au (KDDI) — and the choice between them genuinely affects your experience as a tourist. Not in the cities, where all three are outstanding. In rural Japan, on the Shinkansen, at mountain destinations like Hakone and Nikko — that's where the difference shows up.
Japan's Three Networks — Quick Verdict
| Network | Coverage | Rural Japan | Shinkansen | Tourist Verdict |
|---|---|---|---|---|
| NTT Docomo | Widest nationwide | ✅ Best rural | ✅ Best HSR | 🏆 Best for all Japan |
| SoftBank | Excellent cities | ⚠️ Drops remote | ✅ Good | Good for Tokyo/Osaka focus |
| au (KDDI) | Very good urban | ⚠️ Moderate | ✅ Good | Good second option |
Our Japan eSIM connects to IIJmio roaming on Docomo — Japan's widest network.
Real Speed Data by Location
- Tokyo (Shinjuku, Shibuya, Ginza): 40–120 Mbps on all three networks. Tokyo Metro: Docomo maintains signal on most underground lines.
- Kyoto (Fushimi Inari, Arashiyama): All networks excellent. Docomo handles crowded Arashiyama morning congestion better.
- Hakone Ropeway: Docomo throughout aerial cable car. SoftBank drops on longer spans.
- Hokkaido (Furano, Shiretoko): Docomo excellent — others much weaker in rural Hokkaido. Shiretoko Peninsula: Docomo only in many areas.
Shinkansen Coverage
| Line | Docomo | Notes |
|---|---|---|
| Tokaido (Tokyo–Osaka) | ✅ Excellent | Most covered HSR route in Japan |
| Sanyo (Osaka–Hiroshima) | ✅ Very good | Some tunnel drops near Shin-Osaka |
| Tohoku (Tokyo–Sendai–Aomori) | ✅ Good | Rural north: Docomo essential |
| Hokkaido (Shin-Hakodate–Sapporo) | ✅ Partial | Long tunnels — download maps |
Japan eSIM Plans — Exact Prices
| Plan | Data | Validity | Price | Best For |
|---|---|---|---|---|
| Starter | 1GB | 7 days | $9.99 | Short trip light use |
| Standard | 3GB | 30 days | $6.99 | 5 days Tokyo |
| Traveller | 5GB | 30 days | $9.99 | 10 days Tokyo + Kyoto + Osaka |
| Explorer | 10GB | 30 days | $15.99 | 14 days Japan highlights |
| Nomad | 20GB | 30 days | $26.99 | 21 days+ including Hokkaido |
Frequently Asked Questions
Which network does your Japan eSIM use?
Our Japan eSIM roams on NTT Docomo — Japan's widest network covering all 47 prefectures, rural mountains, Hokkaido wilderness, and Shinkansen routes.
When does my Japan eSIM start billing?
Plan validity starts when the eSIM first connects to a Japanese network — not from purchase date. Install at home, activate when you land.
Does Japan eSIM cover Okinawa and Hokkaido?
Yes. Docomo covers all 47 prefectures including Okinawa's main island and most of Hokkaido. Very remote wilderness (Shiretoko deep trails, Daisetsuzan interior) has limited signal on any network.
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