Best eSIM Plans for Japan 2026

Japan is one of the most connected countries in the world. 5G coverage is excellent in Tokyo, Osaka, Kyoto, and most major cities, with reliable LTE even in rural areas and on the Shinkansen.

Why Use an eSIM in Japan?

Buying a physical SIM at Tokyo Narita or Haneda can take 30–45 minutes in the queue. Pocket WiFi rental costs ¥800–1,200/day and means carrying an extra device. An eSIM is installed before you land — you walk out of the airport already connected.

How Much Data Do You Need?

• Light traveller (maps, messaging, occasional browsing): 3–5GB for 7 days
• Average traveller (social media, Google Maps constantly open, some video): 5–10GB for 7 days
• Heavy user (streaming, video calls, working remotely): 15GB+ or unlimited

Japan's networks are fast — even a modest plan feels quick.

What to Look for in a Japan eSIM Plan

Coverage: Look for plans that use Docomo or SoftBank networks. These have the widest coverage including rural Hokkaido and smaller islands.

Data cap vs unlimited: Unlimited plans often throttle after 1–3GB per day. If you need reliable fast data, a capped plan with a generous allowance may actually perform better.

Validity: Match the plan length to your trip. A 10-day plan for a 7-day trip means wasted days.

Browse Japan eSIM Plans

Roamaly offers Japan plans starting from under £4. Browse Japan eSIM plans →

Frequently Asked Questions

Does an eSIM work on the Shinkansen?

Yes. Japan's bullet trains have mobile coverage through most of the journey, with brief dead zones in tunnels. LTE coverage is generally reliable.

Will my eSIM work in convenience stores and underground?

Coverage is excellent inside most buildings, convenience stores, and underground stations — especially in Tokyo's metro system.