What you’ll learn in this article
- Main Reasons Why eSIM Doesn’t Work for Japan Travel
- Checking Points for iPhone and Android
- Troubleshooting Methods You Can Try Immediately
- Pre-Travel Checks to Avoid Problems
- How to Choose a SIM or eSIM
In Conclusion: Most Problems Stem from Insufficient “Settings” and “Compatible Device” Checks
If your eSIM doesn’t work while traveling in Japan,
it’s often due to incorrect device settings or using a non-compatible or improperly configured eSIM.
Failures and line troubles are rare;
most issues can be resolved yourself with a careful check.
If you want to learn about the basics of eSIMs and how to choose one,
refer to The Ultimate Guide to eSIMs for Visitors to Japan [2026].
Main Reasons Why eSIM Doesn’t Work for Japan Travel
Here are five common causes:
- Device is not eSIM compatible
- eSIM is not properly added or activated
- Mobile data line is not switched
- Activation requirements not met before arriving in Japan
- Data capacity used up or speed limit reached
You can identify the cause by checking these in order.
Checking Points if eSIM Doesn’t Work on iPhone
iPhone users, please check the following:
- Is the eSIM added in “Settings” → “Mobile Data”?
- Is the line in use switched to the Japan eSIM?
- Is mobile data ON?
- Is Airplane Mode OFF?
- Is the iOS not too old?
In many cases,
the problem is forgetting to switch lines.
Checking Points if eSIM Doesn’t Work on Android
Note that Android devices vary greatly by model.
The checking points are as follows:
- Is the device an eSIM-compatible model?
- Is the eSIM displayed in “SIM Card Manager”?
- Is the Japan eSIM enabled?
- Is mobile data ON?
With Android,
it is not uncommon for the device to be eSIM incompatible.
You can find a guide to compatible devices in
The Ultimate Guide to eSIMs for Visitors to Japan [2026]
.
Common Mistakes Made Before Arriving in Japan
The following operations can cause problems:
- Turning on mobile data before arriving in Japan
- Reading the QR code multiple times
- Deleting the eSIM
- Misunderstanding the activation conditions (start date)
Since many eSIMs cannot be reused once deleted,
be careful when deleting.
Troubleshooting Methods You Can Try Immediately
If your eSIM doesn’t work, try the following in order:
- Restart your device
- Turn mobile data OFF and then ON
- Manually switch the line to the Japan eSIM
- Turn Airplane Mode ON and then OFF
- Connect to Wi-Fi and check the settings again
In many cases, this alone will restore the connection.
What to Do If It Still Doesn’t Work
If you still can’t get it to work, here are some options:
- Contact support (often available in English)
- Use a physical SIM card
- Use pocket WiFi temporarily
For physical SIMs and other communication methods,
refer to The Ultimate Guide to SIMs for Visitors to Japan [2026]
for an overview.
Pre-Travel Checks to Avoid Problems
It’s a good idea to check the following before you leave:
- Whether your device is eSIM compatible
- Read the setup instructions in advance
- Save the QR code in a safe place
- Keep a record of support contact information
If you are unsure about the setup method,
it is a good idea to check the SIM registration/setup method summary page in advance.
Summary: Most Problems Can Be Solved by Checking Carefully
- Most eSIM problems are due to setting errors
- For iPhones, line switching is important; for Androids, checking compatible devices is crucial
- Be careful when deleting
- Preparation is the best way to prevent problems
If you are concerned about eSIMs,
including a comparison with SIM cards,
refer to The Ultimate Guide to SIMs for Visitors to Japan [2026]
and choose the communication method that suits you.
Recommended eSIMs/SIMs (space to be filled later)
*Replaced when affiliate program is introduced
- Company A: eSIM for Travelers to Japan (Tentative)
- Company B: SIM card with setup support (tentative)
Comments