Many people may be wondering, "Is it okay to scan the QR code before departure?" or "Should I set it up after arriving in Japan?" after purchasing an eSIM for their trip to Japan.
It is generally recommended to scan the QR code before departure while you have access to a stable Wi-Fi environment. However, depending on the eSIM, the usage period may start from the time of installation or when communication begins, so it is necessary to check the usage conditions in advance.
This article clearly explains the recommended timing for scanning the QR code for the Japan eSIM, important points to check before setting it up, and how to troubleshoot if you encounter issues during setup.
When should I scan the Japan eSIM QR code?
As a rule, it is safer to scan the Japan eSIM QR code in a Wi-Fi environment before departure and add the eSIM to your device.
If you complete the addition of the eSIM before departure, you can smoothly use the internet by simply switching to the Japan eSIM for your mobile data connection after arriving in Japan.
However, the conditions for starting usage vary by product. The main patterns for when usage begins include:
- Usage period starts from the time the eSIM is added to the device
- Starts when connected to a compatible network in Japan
- Starts from a specified start date
- Starts when the first data communication is performed
Some products may have a reduced number of available days if you set it up too early, so be sure to check the usage start conditions in the guidance email you receive after purchase or on the product page.
If you are planning to purchase a Japan eSIM, please check the Japan eSIM product and pricing plans for details on usage days and data capacity. For more information on how to choose a plan, please refer to Comparison of Japan eSIM pricing and plans.
It is recommended to scan the QR code before departure
While you can set it up at the airport after arriving in Japan, it is more reassuring for first-time eSIM users to set it up before departure.
Scanning the QR code may require an internet connection. If you do it before departure, you can calmly set it up in a stable Wi-Fi environment at home or in a hotel.
Benefits of setting it up before departure
- You can set it up in a stable Wi-Fi environment
- You have time to troubleshoot if any issues arise during setup
- You can use the internet immediately upon arrival in Japan
- You can reduce the hassle of searching for free Wi-Fi at the airport
- You can quickly check maps and transportation information
Especially if you want to use map apps, transit guides, hotel information, or translation apps immediately after arriving in Japan, setting it up before departure is recommended.
If you are setting up an eSIM for the first time, please also check the eSIM setup guide with step-by-step images.
Steps to set up if scanning the QR code before departure
If you are preparing the Japan eSIM before departure, follow these steps to set it up.
- Connect your smartphone to Wi-Fi
- Prepare the QR code you received after purchase
- Select "Add eSIM" from the settings screen of your smartphone
- Scan the QR code
- Confirm that the eSIM has been successfully added
- Keep the Japan eSIM data communication OFF until you arrive in Japan
- After arriving in Japan, set the Japan eSIM as your mobile data connection
- Turn ON data roaming if necessary
The names of the settings screens may differ between iPhone and Android. Additionally, the display may vary depending on the manufacturer and model of Android devices.
If you are unsure whether your smartphone supports eSIM, please check the list of eSIM-compatible devices before setting up.
Is it okay to scan the QR code after arriving in Japan?
Generally, it is not a problem to scan the QR code after arriving in Japan.
However, you may need a Wi-Fi connection to scan the QR code. The free Wi-Fi at the airport may become unstable due to congestion or connection issues, which could delay the setup process.
If you plan to set it up after arriving in Japan, prepare the following items in advance:
- A separate device to display the QR code
- A printed copy of the QR code
- Manual setup information for the eSIM
- Your order number from the purchase
- Contact information for support
If you are setting it up with only one smartphone, you cannot display the QR code on the same smartphone screen and scan it with that device's camera. In that case, you will need to use manual input, scan from a photo app, or display the QR code on another device.
Since the methods may vary by device, it is recommended to check the setup instructions in advance.
Points to check before scanning the QR code
Before scanning the eSIM QR code, please check the following items.
1. Check the conditions for starting usage
The most important thing is to confirm when the usage period for the eSIM begins.
If the usage starts when connected to a Japanese network, it is generally fine to add the eSIM before departure. On the other hand, if the usage period starts from the time it is added to the device, be careful not to set it up too early.
2. Check if your smartphone supports eSIM
Not all smartphones can use eSIM. Even with the same model name, some may not support eSIM depending on the country of sale or carrier.
Additionally, devices that are SIM-locked may not be able to use the purchased eSIM. Please check the eSIM compatibility and SIM lock status of your device in advance.
3. Set it up in a stable Wi-Fi environment
If the internet connection drops while downloading the eSIM, the setup may not complete successfully.
Use stable Wi-Fi at home or in a hotel rather than public free Wi-Fi whenever possible.
4. The QR code may only be usable once
For security reasons, the eSIM QR code may only be usable once.
If you delete the eSIM from your device after adding it once, you may not be able to reconfigure it with the same QR code. Even if you cannot connect, do not delete the eSIM immediately; first, check the setup details.
5. Do not delete the eSIM until setup is complete
After adding the eSIM, do not delete it just because you cannot connect immediately.
You may be able to connect by reviewing the settings for mobile data connection, data roaming, network selection, APN, etc.
If you cannot connect after setup, please check troubleshooting for when the Japan eSIM does not connect.
6. Do not share the QR code with others
The QR code contains important information for adding the eSIM to your device. Avoid posting it on social media or forwarding it to third parties.
If someone else uses your QR code, you may not be able to set up the eSIM on your device.
Does data communication start just by scanning the QR code?
Simply adding the eSIM by scanning the QR code does not necessarily mean that data communication will start immediately.
Generally, the following settings are required after arriving in Japan:
- Turn ON the added Japan eSIM line
- Select the Japan eSIM for mobile data communication
- Turn ON data roaming if necessary
- Turn OFF data roaming for the main line
If data roaming is ON for the SIM card you usually use abroad, you may incur high overseas roaming charges. Be sure to check which line is designated for mobile data communication when using the Japan eSIM.
Causes and solutions if you cannot scan the QR code
If you cannot scan the QR code, please check the following items in order.
The QR code is unclear
You may not be able to scan the QR code if the image is small, blurry, or the screen is dark.
Try displaying the QR code larger on another device or increase the brightness and scan it again.
The QR code is displayed on the same device
If the smartphone you are setting up is the same one displaying the QR code, you cannot usually scan it with the normal camera.
Use a computer or another smartphone to display it, or use the manual setup information. Depending on the model, you may be able to scan a saved QR code image from the photo app.
The QR code has already been used
If the QR code has already been used on another device or if you deleted the eSIM after adding it once, it may not be reusable.
In this case, please prepare your order number, the device used, and any error messages displayed, and contact support.
The device does not support eSIM
If you do not see options like "Add eSIM" or "Add mobile data plan" in the settings menu, your device may not support eSIM.
Check not only the model name but also the model number and the country/region where you purchased it.
The internet connection is unstable
A stable internet connection is required to download eSIM information.
Try turning Wi-Fi OFF and ON, connecting to a different Wi-Fi, or restarting your device.
What to do if you cannot connect after scanning the QR code
Even if the eSIM has been added successfully, you may not be able to connect to the internet after arriving in Japan.
In that case, please check the following items:
- Is the Japan eSIM line ON?
- Is the Japan eSIM selected for mobile data communication?
- Is data roaming ON?
- Is airplane mode OFF?
- Are you receiving a compatible network?
- Is APN setting required for the product?
- Are there any issues with the start date or available area?
After changing the settings, you may be able to connect by turning airplane mode ON and then OFF, or by restarting your smartphone.
For detailed confirmation steps, please refer to Japan eSIM setup and support information.
How much data capacity do you need for your trip to Japan?
When choosing a Japan eSIM, be sure to check not only the method for setting up the QR code but also the data capacity you will need during your trip.
The required data capacity can vary significantly depending on whether you primarily use maps, messaging, and web searches, or if you watch videos and post videos on social media.
You can check the estimated data usage by purpose at Estimated data usage.
If you need an eSIM with a phone number
General travel eSIMs are usually data-only and may not support voice calls or SMS using a regular phone number.
If you need a phone number in Japan or want to use SMS authentication, please check the support for calls and SMS before purchasing.
If you need a phone number, please also check the eSIM plans with a phone number.
Frequently Asked Questions about the Japan eSIM QR Code
How many days before departure should I scan the QR code?
If there are no issues with the usage start conditions, it is safe to set it up a day or a few days before departure. However, for products where the usage period starts from the time of adding the eSIM, please follow the guidance from the seller.
Is it okay to turn ON data roaming before arriving in Japan?
To avoid accidental connections or unintended communication, it is safer to keep the Japan eSIM line and data roaming OFF until you arrive in Japan. Please turn ON the necessary settings after arriving in Japan.
Can I set it up from a screenshot of the QR code?
If the QR code is displayed clearly, it may be possible to set it up from a screenshot. However, you cannot scan a QR code displayed on the same smartphone with the normal camera. Please use the photo app's scanning feature, another device, or manual input.
Can I reconfigure the eSIM after deleting it once I have scanned the QR code?
Since the same QR code may not be reusable, it is generally recommended not to delete it. If deletion is necessary, it is advisable to confirm with the seller's support in advance.
What should I do if I cannot connect immediately after arriving in Japan?
Check the mobile data connection, data roaming, network selection, etc., and try toggling airplane mode ON and OFF or restarting your device. If you still cannot connect, please check the troubleshooting page.
For other questions, please also refer to Frequently Asked Questions about eSIM.
Summary: Check the usage start conditions and scan the QR code before departure
It is recommended to scan the Japan eSIM QR code before departure while you have access to stable Wi-Fi and complete the addition to your device.
However, the timing for when the usage period starts varies by eSIM. Before setting it up, be sure to check whether it starts at installation, on a specified date, or when connecting to a Japanese network.
Also, since the QR code may only be usable once, it is important not to delete the eSIM immediately if you cannot connect after setup.
If you want to review the basic selection, purchase, and setup methods for the Japan eSIM, please check the Complete Guide to Japan eSIM.
