eSIM for Japan | How to Choose and Use eSIM in Japan

What is an eSIM? Basic Mechanism and Advantages

Basic Concept of eSIM

An eSIM (embedded SIM) is a small chip built directly into devices like smartphones and tablets, eliminating the need for a physical SIM card.

Unlike traditional plastic SIM cards, the eSIM is integrated into the device, allowing you to use communication services by simply downloading the mobile carrier's profile information.

The most significant feature of an eSIM is that the contract and activation process can be completed entirely online without the need to swap physical cards.

This allows you to start using mobile data communication immediately upon arrival in a new country.

Differences from Traditional SIM Cards

Main Advantages of eSIM

1.Rapid Activation: Completed online, ready to use in as little as a few minutes.

2.No Physical Card Needed: No risk of losing or damaging the SIM card.

3.Multiple Profile Management: Manage multiple eSIM profiles on a single device.

4.Eco-friendly: Reduces the use of plastic SIM cards.

5.Ideal for Travelers: Purchase and set up local eSIMs before your trip.

Pros and Cons of eSIM for Japan

Benefits of eSIM for Foreign Visitors to Japan

1.Advance Preparation: Can be purchased and set up before arriving in Japan, avoiding long lines at the airport.

2.High-speed and Stable Connection: Access networks of major Japanese carriers.

3.Cost Efficiency: Significantly cheaper than roaming charges.

4.Diverse Plans: Various options for duration and data capacity, from short to long stays.

5.Nationwide Coverage: Stable communication in major cities, rural areas, and tourist spots.

Disadvantages and Constraints to Consider

1.Device Compatibility: Not all smartphones support eSIM.

2.Technical Hurdles: Setup may require some technical knowledge.

3.Support During Troubles: Language support or 24-hour assistance may not always be available.

4.Quality Variation by Provider: Communication speed and coverage vary depending on the provider.

5.SIM Lock: Some devices may be SIM-locked, preventing the use of eSIM.

Recommended eSIM Provider

A highly-rated eSIM provider among foreign visitors to Japan is GTN Prepaid eSIM.

Key highlights include the ease of application and the availability of large data capacities.

GTN Prepaid eSIM

GTN Prepaid eSIM offers prepaid SIMs for data-only or voice + data, with durations ranging from a minimum of 7 days to a maximum of 90 days.

You can apply with just your passport. It features 5G/LTE networks and 8-language customer support. Please note that after the data is used up, speeds will be reduced and extensions are not possible, making it ideal for short- to medium-term stays.

運営会社	Global Trust Networks Co., Ltd.
料金	Data-Only SIM / eSIM Data Capacity Duration Price 10 GB 30 Days 3,000 JPY 30 GB 7 Days 3,000 JPY 50 GB 30 Days 5,000 JPY 135 GB 90 Days 10,000 JPY   Voice + Data SIM Data Capacity 30 Days 60 Days 90 Days 10 GB 8,250 JPY 14,850 JPY 21,450 JPY 30 GB 12,100 JPY 19,800 JPY 27,500 JPY •Domestic call charges are 22 JPY per 30 seconds (tax included). SMS charges range from 3.3 to 33 JPY (tax included) per message (domestic). •Information as of November 2025.
公式HP	https://www.gtn-mobile.com/

How to Check eSIM Compatibility

List of Major Compatible Models

iPhone

•iPhone XS / XS Max / XR and later models

•Requires iOS 12.1 or higher

Android

•Google Pixel 3 and later

•Samsung Galaxy S20 / Note 20 and later

•OPPO Find X3 Pro and later

•Sony Xperia 10 III and later

•Many others (depending on the manufacturer)

How to Check if Your Device is Compatible

For iPhone

•Go to "Settings" → "Cellular". If you see the "Add Cellular Plan" option, it is compatible.

•Alternatively, go to "Settings" → "General" → "About" and check if an EID is displayed.

For Android

•Go to "Settings" → "Network & Internet" → "Mobile Network". If you see the "Download a SIM instead?" or "Add Mobile Plan" option, it is compatible.

•Alternatively, enter *#06# in the phone app and check if an EID is displayed.

Checking on Manufacturer Websites:

•Check the specs on the device manufacturer's website.

•It is compatible if "eSIM supported" or "Dual SIM (nano-SIM and eSIM)" is mentioned.

eSIM Setup Procedures

From Purchase to Use

1.Provider Selection and Plan Purchase:

•Choose a plan that fits your travel duration and data usage.

•Complete the purchase online (credit cards are common).

2.Receive QR Code or Activation Code:

•In most cases, a QR code or activation code is sent via email after purchase.

•Some providers allow activation through a dedicated app.

3.Install eSIM Profile:

•Perform the setup while connected to a Wi-Fi environment.

•Scan the QR code or enter the activation code.

4.Confirm Network Settings:

•Set data roaming to "On."

•Set the preferred line for mobile data.

•Check APN settings (if necessary).

Setup for iPhone

1.Connect to Wi-Fi.

2.Tap "Settings" → "Cellular" → "Add Cellular Plan."

3.Select "Use QR Code" and scan the QR code provided by the provider.

4.Follow the on-screen instructions to complete the setup.

5.Enter a label for the eSIM (e.g., "Japan Travel").

6.Confirm that the eSIM is active in "Settings" → "Cellular."

Setup for Android

1.Connect to Wi-Fi.

2.Tap "Settings" → "Network & Internet" → "Mobile Network" → "+" or "Download a SIM instead?".

3.Select "Scan QR Code" and scan the QR code provided by the provider.

4.Follow the on-screen instructions to complete the setup.

5.Enter a profile name (e.g., "Japan Travel").

6.Confirm that the eSIM is enabled in "Settings" → "Network & Internet."

Communication Networks and Coverage in Japan

Major Carriers in Japan

There are three main major carriers in Japan, each operating its own network.

•NTT DOCOMO: Japan's largest carrier with the widest coverage. It offers relatively stable communication even in mountainous areas and remote islands.

•KDDI (au): The second-largest carrier, strong in high-speed communication in urban areas. It provides a stable environment even at tourist spots.

•SoftBank: Deploys high-speed services primarily in urban centers and has strengthened coverage in some tourist areas.

•Rakuten Mobile: A relatively new carrier expanding its own network. While its coverage still lags behind the other three, it provides services using partner networks.

Area Coverage and Speed

In major cities and tourist spots in Japan, 4G/LTE is available in most cases, and 5G is gradually expanding. Stable communication can be expected in the following areas:

•Metropolitan Areas (Tokyo, Osaka, Nagoya, etc.): All carriers provide high-speed and stable networks.

•Major Tourist Spots (Kyoto, Hiroshima, Sapporo, Fukuoka, etc.): Good coverage can be expected.

•Shinkansen Lines: Major carriers ensure coverage along almost all lines.

•Regional Cities: Major carriers provide trouble-free communication in most regional cities.

However, communication may become unstable in the following locations:

•Mountainous Areas and Remote Islands: Coverage may be limited due to terrain.

•Underground Facilities and Tunnels: Signals may be hard to reach.

•Crowded Tourist Spots: Temporary network congestion may occur.

Recommended eSIM Selection by Travel Type

Short-term Sightseeing (Within 1 Week)

Recommended Providers

Airalo, Japan Wireless, IIJ Japan Travel SIM

•Selection Points:

•Data Capacity: Approx. 1GB per day (assuming maps, SNS, and email).

•Duration: A plan that matches your exact stay.

•Price: Daily plans are often more economical.

•Ease of Setup: Choose services that can be set up immediately via QR code.

•Plan Examples:

•Airalo Sakura Mobile: 5GB for 5 days (approx. 2,000 JPY)

•Japan Wireless: Unlimited for 5 days (approx. 2,400 JPY)

•IIJ Japan Travel SIM: 3GB for 7 days (approx. 2,000 JPY)

Medium- to Long-term Stay (1 Week to 1 Month)

Recommended Providers

Mobal, Rakuten Mobile, World eSIM, JapanConnect eSIM

•Selection Points:

•Data Capacity: 5GB or more per week (assuming video streaming and frequent SNS).

•Stability: Plans without speed limits are preferable for long-term use.

•Support: Providers with English-speaking customer support.

•Voice Function: Consider plans that provide a Japanese phone number if needed.

•Plan Examples:

•Mobal: Unlimited for 30 days (approx. 7,000 JPY)

•Rakuten Mobile: 20GB for 30 days (approx. 3,278 JPY, with phone number)

•World eSIM: 12GB for 30 days (approx. 4,000 JPY)

•JapanConnect eSIM: 30GB for 30 days (approx. 5,000 JPY)

Business Use

Recommended Providers

Rakuten Mobile, Mobal, GTN PREPAID eSIM

•Selection Points:

•Stability: Reliable communication for business meetings and video conferences.

•Large Data: High-capacity plans suitable for remote work and file sharing.

•Phone Number: Plans with a phone number if domestic calling is required.

•Customer Support: Comprehensive support for technical issues.

•Plan Examples:

•Rakuten Mobile: Unlimited for 30 days (approx. 3,278 JPY, with phone number)

•Mobal: Unlimited for 30 days (approx. 7,000 JPY, excellent English support)

•GTN PREPAID eSIM: 30GB for 30 days (approx. 5,800 JPY, support for foreigners)

Comparing and Choosing Price Plans

Choosing by Data Capacity and Duration

Tips to Maximize Cost Performance

•Understand Your Usage Pattern: Refer to your data usage from past trips and check if Wi-Fi is available at your destinations.

•Check Plan Flexibility: See if there are data top-up options, if the duration can be extended, or if unused data carries over.

•Check for Hidden Costs: Some providers charge initial setup fees. Check conditions for speed throttling and any extra fees for support.

•Consider Share Plans for Groups: Some providers offer plans where data can be shared across multiple devices, which can save costs for families or friends.

Troubleshooting eSIM Issues

Common Problems and Solutions

Cannot Connect

•Ensure "Data Roaming" is turned ON.

•Toggle Airplane Mode ON and then OFF.

•Confirm "Mobile Data" is enabled and the correct eSIM is selected.

Slow Speed

•Consider the impact of crowded locations or peak times.

•Check if you have reached your data limit (throttling may occur).

•Verify APN settings or try manually selecting the network type (4G/LTE/5G).

Cannot Download Profile

•Retry in a stable Wi-Fi environment.

•Check if your device has enough storage and if the software is up to date.

•Request a new QR code from the provider.

Sudden Disconnection

•Reset network settings.

•Delete and reinstall the eSIM profile (requires Wi-Fi).

•Restart your device or manually select a network provider.

Tips for Prevention

•Before Departure: Complete the eSIM setup, save screenshots of the QR code, and keep the provider's support information handy.

•Have a Backup Plan: Check for free Wi-Fi spots at airports and tourist areas. Consider multiple eSIM options or download offline maps.

•Optimize Settings: Limit unnecessary background data, upload photos/videos manually or over Wi-Fi at night, and use apps to monitor data usage.

Frequently Asked Questions (FAQ)

Basic Questions

Q: Do I need to unlock my smartphone to use an eSIM in Japan?

A: Yes, in most cases, your device must be SIM-unlocked. We recommend checking with your home carrier and completing the unlock process before departure.

Q: Can I get a Japanese phone number with a Japanese eSIM?

A: Not all eSIM services provide a Japanese phone number. If you need one, you must choose a plan that includes it, such as Rakuten Mobile. Most tourist eSIMs are data-only.

Q: When is the best time to activate the eSIM?

A: While many can be activated anytime after purchase, it is most efficient to activate it upon arrival in Japan. You can set it up beforehand and enable it when you land.

Technical Questions

Q: Can I use an eSIM on older iPhone models (before iPhone XS)?

A: Models before iPhone XS/XR do not support eSIM. You can use it on iPhone XS/XR and later models.

Q: Can I maintain my home country's connection while using an eSIM?

A: Yes, if your smartphone supports Dual SIM, you can use the Japanese eSIM and your home SIM simultaneously. You can condiv which SIM to use for calls and which for data.

Q: Can I reinstall the eSIM with the same QR code after deleting it?

A: In many cases, yes. However, some providers have expiration dates or limits on the number of reinstalls, so it's best to save the QR code image.

Service-Related Questions

Q: Is English support available if I have technical issues?

A: Major providers for foreign visitors offer English support. Mobal, Japan Wireless, and World eSIM are particularly known for their English assistance.

Q: Can I buy more data if I run out before the plan ends?

A: Most providers allow you to purchase additional data packages. Check if this option is available when choosing your plan.

Q: Can I get a refund for an unused eSIM?

A: Most providers do not offer refunds once purchased, especially after activation. It's important to choose a flexible plan if your itinerary might change.

Summary

eSIM for Japan is a convenient and flexible communication method for foreign visitors. By choosing the best plan for your travel duration and usage pattern and understanding the setup process in advance, you can make your stay in Japan even more fulfilling. With stable coverage in major tourist areas, you can fully utilize your smartphone for maps, SNS, and online reservations.

Before your trip, confirm your device's compatibility and select the right provider and plan. Also, keep this troubleshooting information handy just in case. Enjoy your stay in Japan!