Guide to Google Fi in Japan | Everything You Need to Know!

Landing in Japan and expecting Google Fi in Japan to kick in like magic? It might…until your data slows to a crawl, streaming fails, or your SIM quietly deactivates after 90 days.

Yep, using Google Fi in Japan has a few hidden catches that can turn your trip from smooth to stressful.

Stick around before you rely on it for Google Maps, Instagram, or that late-night ramen hunt. We break down how Google Fi performs in Japan, what it really costs, and when it’s smarter to grab a Japan-ready SIM or eSIM that just works—no surprises. 

Table of Contents

• Overview of Google Fi plans in Japan
• Google Fi in Japan Coverage
• Google Fi in Japan: Pros and Cons
• For Travelers, Business Trips, and Short Stays
• For Stays of 3+ months
• Why Choose Sakura Mobile? Affordable & Flexible Data Options
• Maximize Your Data with These Tips
• Check This Before Your Trip
• Enjoy Your Trip to Japan

TL;DR:

1) Short Trips (<3 months):  If you already have a Google Fi Unlimited Premium plan, it will work in Japan for basic data and texting. But for better value and more data, a Japanese prepaid SIM or eSIM—like Sakura Mobile’s often makes more sense.
2) Longer Stays (3+months): Visiting for work, study or a long vacation? Google Fi in Japan isn’t built for extended use. A local plan or Pocket WiFi is more reliable. Sakura Mobile offers unlimited data, a Japanese phone number, and full English support for a smoother long-term experience.

3) Coverage & Support: While Google Fi roams on Japanese networks, it doesn’t provide a clear coverage map or local support. In contrast, Sakura Mobile’s coverage is on the docomo network (99% of Japan) and offers real human English support when needed.

Overview of Google Fi plans in Japan

If you’re considering using Google Fi in Japan, two plans actually work overseas. Here’s what they look like:

• Unlimited Plus Plan ($65/month):

Best for short trips or frequent travelers who stream and browse a lot. Includes up to 50 GB of high-speed data in Japan, before slowing. Great for heavy data use on short trips or frequent international travel.

• Flexible Plan ($20 base + $10/GB):

Idea if you use limited data. You only pay for what you use, capped at $80/month after 6 GB. High-speed data works up to 15 GB abroad.

Both plans offer free texting abroad and charge .20 cents/minute for international calls (outside the US, Canada, and Mexico).

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🌎Google Fi in Japan Coverage

Google Fi in Japan connects through major local carriers, like docom, SoftBank, and au, so coverage is generally strong in cities, suburbs, and tourist areas.

However, Google Fi doesn’t publish a detailed coverage map for Japan, making it unclear where you’ll get service.

What we found:

We tested Google Fi’s coverage by checking 10 random addresses from Hokkaido to Okinawa—all were marked as “Covered.”

In real-world use:

• ✅Cities and towns: Usually reliable signal.
• ⚠️Remote areas, tunnels, and mountains: Possible dropouts or weak coverage.

5G Coverage in Japan

Japan has rapidly expanded its 5G infrastructure, especially in major cities. Here’s how local carrier coverage stacks up:

Google Fi connects to these networks, but coverage in rural or mountainous regions may still be limited.

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Google Fi in Japan: Pros and Cons

Google Fi in Japan can be a solid option— but only for short trips and light usage.

✅Best for Google Fi:

• Short Visits (Under 90 Days): If you’re already on the Unlimited Premium Plan, Google Fi works in Japan with no extra roaming fees. You’ll get high-speed data (throttled after ~50 GB) and can stay connected without switching SIMs.
• Digital Nomads:  Google Fi’s global coverage makes it convenient to hop between countries.

❌Not Ideal For:

• Extended Stays (3+ Months): Google Fi must be used “primarily in the U.S.”— so extended use in Japan can violate their terms and risk suspension. 
• Heavy Data Users: The Flexible Plan becomes expensive quickly— data overages add up fast. 
• Need a Japanese Phone Number: Google Fi gives you a U.S. number, which isn’t good for local apps, banking, or job hunting in Japan.
• Local Customer Support: Google Fi’s U.S.-based team can’t always help with network issues unique to Japan.

For travelers, business trips, and short stays

Google Fi in Japan isn’t always the best deal for short stays, business trips, or vacations.

A Japanese prepaid SIM/eSIM often gives you faster speeds and better value.

Sakura Mobile offers unlimited data travel SIMs and eSIMs with full English support:

• ✅7-day unlimited 5G eSIM: 5,500 JPY
• ✅7-day unlimited 4G eSIM: 4,620 JPY
• ✅8-day unlimited 4G SIM: 4,950 JPY

*Tax included in prices above

These plans provide unlimited high-speed 5G/4G LTE data on docomo’s reliable network.

Compared to Google Fi’s Unlimited Premium plan at $65/month (with speeds slowing down after ~50 GB), Sakura Mobile’s 5G eSIMs offer more for lower prices.

🚚Plus, we’ll deliver your eSIM directly to your hotel or airport, so you’ll be connected immediately.

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For Stays of 3+ Months

If you’re moving to Japan for work, study or an extended stay, Google Fi in Japan isn’t built for long-term use.

While the Unlimited Premium plan might sound tempting, Google Fi’s terms require your usage to be “primarily in the U.S.”

Using it in Japan for over 90 days may lead to account suspension.

❌Risk: Some users report that Google Fi roaming doesn’t activate unless the SIM has been used in the U.S. first. You could arrive in Japan with no service.

✅Better Option: Go with Sakura Mobile’s long-term SIM or eSIM plans—made for residents and fully supported in English. 

Current Voice + Data SIM plans (with a Japanese phone number): 

• 5GB data for 3,279 JPY (~$23)
• 25GB data for 4,378 JPYY (~$30)
• 40GB data for 5,478 JPY (~38)

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Why Choose Sakura Mobile?🌸

While Google Fi might work for quick visits in Japan, it’s not built for reliable, long-term use. Sakura Mobile offers better coverage, flexibility, and peace of mind.

Here’s why Sakura Mobile makes more sense: 

💸Lower Costs: Google Fi’s Unlimited Premium plan costs $65/month with throttling after 50 GB. Sakura Mobile’s unlimited 5G eSIM starts at just ￥4,400 (~$30) with no speed caps.

📶For Heavy Data Users: Sakura Mobile’s 5G eSIM offers high-speed data with no daily limits or FUP restrictions—ideal for streaming, navigation, and sharing your trip in real time. 

🧳Perfect for Travelers: If you don’t need your U.S. number, apps like WhatsApp, LINE, or Messenger work seamlessly over a data-only eSIM.

📵Avoid Account Issues: Google Fi’s terms require primary usage in the U.S. Extended use in Japan may result in suspended service. With Sakura Mobile, you can travel throughout Japan without worry.

📲Stay connected without compromise.

👉Browse travel eSIM/SIM plans.

Want to learn more about data options in Japan?

Check out: Japan Prepaid SIM: Limited vs. Unlimited Plans

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📶Maximize Your Data with These Tips

Traveling with limited data? Here are some simple ways to save data and make the most of your connection:

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⚠️Check This Before Your Trip

Is your phone compatible with Japanese frequency bands?

Before heading to Japan, it’s essential to check if your phone is compatible with the country’s frequency bands.

To ensure compatibility with Sakura Mobile, you can check your device against our compatibility list:

• Sakura Mobile physical SIM compatibility
• Sakura Mobile eSIM compatibility

If your device isn’t listed, don’t worry! Our customer support team here to help! Just reach out with your questions, and we’ll get back to you by the next day.

💬Contact Us

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Enjoy Your Trip to Japan

With so many different foods to taste and places to visit during your trip to Japan, your phone not working should be the last thing on your mind.

We recommend getting Sakura Mobile’s Travel SIM/eSIM to be as safe as possible and enjoy your trip to the fullest.

Ready to Stay Connected?

Try Sakura Mobile’s 5G Unlimited Data eSIM!🌸

• 🚀Unlimited high-speed 5G– No fair usage policies, no slowdowns
• 🌍Instant connection – Pre-order online, scan a QR code, and you’re ready to go.
• 📱Perfect for travel– Stream, navigate, upload, and stay in touch without limits.
• 🧠Worry-free experience– No need to monitor usage or top-up.
• 📦Convenient delivery– Get your eSIM via email or have a physical SIM shipped to your hotel or airport.

With Sakura Mobile, you get more data, speed, and peace of mind than Google Fi in Japan.

Want a Lighter Option? Try Our 4G Travel SIM/eSIM