What's The Best Unlimited Data eSIM for Japan?

Planning a trip to Japan? Whether you're staying for just a few days or exploring the country (or continent) for several weeks, choosing the right eSIM for Japan means even the most disorganised person can do and see more. From short business trips to extended cultural immersions, there’s a plan to suit every traveller.

Stay connected with all the data you need, and reliable coverage on fast networks like KDDI and NTT Docomo.

Sim Local only partners with trusted networks like au Japan to give you that ‘just like home’ connection — wherever you are. 

_{Why choose an eSIM?}

1. You can activate one instantly, anywhere: eSIMs can be activated as soon as you land, saving you the hassle of finding a local SIM card or dealing with physical cards.
2. Stop worrying about roaming charges: With a few taps of your phone settings, you make the quick switch to a pay-as-you-go plan during your trip and stop relying on your home plan's data roaming. 
3. Your phone probably supports eSIM: Most smartphones are compatible with eSIM technology nowadays. You can confirm here. 

^{Best eSIMs for Japan}

Here's our list of the best eSIMs for Japan depending on your length of stay. au by KDDI is one of Japan’s biggest and most reliable mobile networks, known for excellent nationwide coverage and fast data speeds — especially outside the big cities where some networks drop off. Trusted by millions in Japan, au offers excellent connectivity for both locals and visitors.

Unlike international providers like Holafly or Ubigi, you’re connecting straight to the source for faster, stronger coverage at cheaper prices!

^{For Short Stays (3–4 days)}

Some travellers, especially those from nearby countries in Asia, may visit Japan for a shorter trip (maybe a long weekend), usually to focus on one or two cities, such as Tokyo or Osaka.

Japan Unlimited - 4 Day

AU

Unlimited

$13.00

4 Days

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Japan Unlimited – 4-Day eSIM

Stay online during your short visit to Japan with this 4-day eSIM plan from au by KDDI, priced at $13 USD. Enjoy unlimited data on one of Japan's most popular networks, plus 3GB for data tethering if you need to share your connection.

^{For 1 Week (7–10 days)}

Most first-timers go to Japan for at least a week, giving themselves a few days to explore Tokyo, including iconic neighbourhoods like Shibuya, Shinjuku, and Asakusa. Kyoto is usually on the itinerary too, known for its temples, shrines, and traditional culture, often requiring another 2–3 days.

Japan Unlimited - 10 Day

AU

Unlimited

$26.00

10 Days

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Best Value

Japan Unlimited – 10-Day eSIM

For $26, this 10-day eSIM from au by KDDI gives you unlimited smartphone data while you explore Japan. It also allows tethering up to 3GB on the KDDI network.

^{For 10–15 days}

A two-week trip provides a more relaxed itinerary, with time to explore additional cities and regions beyond the Tokyo-Kyoto-Osaka triangle, such as Hiroshima and Miyajima. Depending on the season, Hokkaido or Okinawa are also popular for exploring Japan’s northern or southern islands for skiing, beaches, and more. Looking for more things to do? How about Nikko, Kanazawa, or the Japanese Alps?

Japan Unlimited - 15 Day

AU

Unlimited

$39.00

15 Days

Buy now

Top Seller

Japan Unlimited – 15-Day eSIM

Enjoy unlimited data for 15 days on your trip to Japan with this $39 eSIM plan, also running on the KDDI network. Another great value plan from au, you can stay connected throughout your journey, with tethering available up to 3GB for hotspot sharing.

^{For 3 Weeks or More}

Longer stays, from three weeks to a month, allow you to dive deeper into Japan’s culture, history, and natural beauty. Go off the beaten path and explore places like Kyushu, the southern island with hot springs (like Beppu) and volcanoes, Shikoku, known for the Shikoku Pilgrimage and beautiful landscapes, or Tohoku in the northern regions. Think: beautiful nature, onsen towns, and incredible history. There’s even time for ceremonial practices like tea ceremonies! 

Japan 20 GB

Smartroam

20GB

$27.75

30 Days

Buy now

Top Seller

Japan 20 GB – 30 Day eSIM

For $27.50, this 30-day Smartroam eSIM provides 20 GB of data, running on the NTT Docomo network to ensure the best possible connectivity. Data tethering and hotspot capabilities are included. 

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