Yes. You can receive Taiwan SMS messages (including verification codes) for free while in Japan.

📌 Explanation:
• Taiwan mobile numbers (such as Chunghwa Telecom / Taiwan Mobile) can still receive SMS messages while you are in Japan.
• Even without applying for international roaming, SMS reception usually works as long as the SIM card remains active.
• Receiving SMS messages generally does not incur any charges (actual conditions may vary depending on your mobile carrier).

📌 Dual SIM Settings (for both Android and iPhone):
• Keep both your original SIM (Taiwan number) and JB SIM enabled at the same time.
• For calls and SMS, we recommend keeping your original SIM (SIM1).
• Switch mobile data to the JB SIM (SIM2) for internet access.
• The same settings apply when using eSIM, allowing both SIMs to be used simultaneously.

📌 Recommendation:
• Switch mobile data to the JB SIM after arriving in Japan.
• This helps prevent accidental roaming charges from using mobile data on your original SIM.

To avoid accidentally using your original SIM and incurring international roaming charges, please follow the settings below:

📌 Basic Settings
• Switch Mobile Data to the SIM/eSIM you use in Japan.
• Turn off the “Allow Mobile Data Switching” function.
• This prevents your device from automatically using your original SIM for internet access.

📌 SMS Information
• You can continue to receive Taiwan SMS messages normally (usually free of charge).
• SMS charges from other countries depend on the regulations of your original mobile carrier.

📌 To completely avoid roaming charges, you can turn off your original SIM:

【iOS Devices】
Settings → Cellular → Select your original SIM → Turn off “Turn On This Line”

【Android Devices】
Settings → Connections → SIM Card Manager → Select your original SIM → Turn off

📌 Recommendation
If you do not need to use your original phone number, we recommend turning off your original SIM completely to prevent any accidental roaming charges.

Yes, you can.

As long as your SIM/eSIM is still within the validity period, you can continue using it when you re-enter Japan, even if you temporarily leave Japan.

📌 After returning to Japan:
• Turn on Mobile Data
• Switch Mobile Data to the JB SIM/eSIM
• Wait for your phone to reconnect to the Japanese mobile network

There is no need to apply again or reinstall the SIM/eSIM. It can be used normally as long as it remains within the validity period.

If you are unable to complete activation immediately after arriving in Japan, please connect to the airport’s free Wi-Fi first and contact our customer support. We will assist you in checking your settings and activation status.

• New Chitose Airport
https://www.new-chitose-airport.jp/ja/service/internet_fax_copy/lan/

• Hakodate Airport
https://www.airport.ne.jp/facility/wifi/

• Sendai Airport
https://www.sendai-airport.co.jp/service/wifi.html

• Narita International Airport
https://www.narita-airport.jp/jp/service/svc_33_wire

• Haneda Airport
https://tokyo-haneda.com/service/facilities/wireless_lan.html

• Chubu Centrair International Airport
https://www.centrair.jp/service/wireless-lan.html

• Kansai International Airport
https://www.kansai-airport.or.jp/service/internet/06.html

• Fukuoka Airport
https://www.fukuoka-airport.jp/service/wifi01.html

• Aso Kumamoto Airport
https://www.kumamoto-airport.co.jp/facilities/kumamoto-free-wi-fi/

• Naha Airport
https://www.naha-airport.co.jp/service/wifi/wifi-spot/

📌 Recommendation
Before departure, please save screenshots of our customer support contact information and your order details so that you can quickly receive assistance after arriving in Japan.

📌 JB eSIM
Since the eSIM activation time can be determined by the customer, we recommend completing the eSIM issuance process after confirming that your flight will depart as scheduled.

• eSIM not yet issued: You can keep it and use it at a later time.
• Activation URL deleted: You can request a new Activation URL through our official LINE account.

📌 JB SIM Card
As long as the SIM card has not been inserted into a device and has not connected to the Japanese Docomo network, it will not be activated and can be kept for your next trip to Japan.

📌 JB Voice SIM / eSIM
Since the Japanese phone number application process begins immediately after the order is submitted, cancellations or refunds are generally not available once the application has been completed.

If you are unable to travel to Japan due to a flight cancellation, please contact us through our official LINE account. We will assist you in confirming the available options and provide further support.

🅰️ Yes, it’s fine.
Since our company’s SIM card is a product from a Japanese telecom provider and not an international roaming type, it will not be activated when inserted into the phone outside of Japan, as it won’t be able to receive the docomo signal from Japan.
To avoid forgetting the SIM ejector tool when traveling abroad or accidentally losing the SIM card while out, we recommend inserting the SIM card into the phone ahead of time.
For dual-SIM phones, typically the SIM card you’re using is inserted in the SIM1 slot, so you can insert the Japanese SIM card into the SIM2 slot as a backup.
※The SIM card will display “No Service/Unknown Number”.

🅰️Since physical SIM cards do not provide online real-time data usage checking services, you need to use the statistics feature on your phone or tablet. Please refer to the “How to check your mobile data usage“

🅰️📢The 6/8/16/31days unlimited SIM cards cannot be extended or topped up. The fixed data SIM cards can have their validity period extended or additional high-speed data added. Please refer to the 🛒SIM_recharge/extension

※Make sure to purchase the extension or top-up products online within the validity period.

※If it is within 7 days after the validity period has expired, top-ups are possible, but the remaining data will be reset to 0.

※Please use your phone or tablet’s statistics feature to check your data usage. Refer to “How to check your mobile data usage”

• You can top up or extend within the validity period.
• Remaining data and newly added data are treated the same; there is no usage priority between the two.
• There is no limit to the number of top-ups or extensions.
• If you top up within 7 days after the expiration date, the data balance will be reset to zero, but you can continue using the original eSIM or SIM card.
• The extension period is calculated from the 2nd day after the original expiration date, which is considered the first day of the new validity period.
• After purchase, in addition to receiving an email with an electronic receipt, you will also receive a separate activation notice from our company via biz@jbrg.jp.
• You may request a cancellation before receiving the activation notice. However, a 5% processing fee will be deducted to cover credit card company fees.
• If you apply for an extension after 6:00 PM on the last day of validity, please contact customer service for confirmation before making the purchase to avoid delays in processing.
• After the initial validity period ends, the online inquiry system [eSIM Activation URL] will no longer reflect the extended validity or remaining data. Please use your mobile device’s data usage statistics instead.
• All JBeSIM plans are eligible for top-up and extension. JB SIM cards with data capacity (X-GB) can be topped up, while time-based plans (6/8/16/31 unlimited) cannot be extended.

🅰️After updating to iOS 17, there may occasionally be an issue where the signal bars do not display the signal strength, but this does not affect reception. You can try the following methods:

• Restart the iPhone
• Toggle Airplane Mode on and off
• Turn mobile data off and on
• Check for software updates

Regular maintenance hours (Japan Time)

Every Tuesday from 10:00 PM to Wednesday 9:00 AM

■eSIM
During the system maintenance period, issuing eSIM activation QR codes will not be possible.
If the “Issue” button has already been pressed, the status will remain as “Pending.”
You may exit the screen and return later via the link to check the issuance result.
If the activation code has already been issued, you can still proceed with “Add eSIM” and begin using the service, even during maintenance.

■SIM Card
Inserting a physical SIM card into a smartphone or other device during the maintenance period may result in no response.
However, there is no need to worry — the system will automatically complete the activation process in order once maintenance is finished.
SIM cards that are already in use will not be affected.

■Voice SIM Card
Voice SIM cards are pre-activated before delivery and are therefore not affected by system maintenance.

Temporary Maintenance hours (Japan Time)

① Sep. 24, 2025, 10:00 PM ～ Sep. 25, 2025, 9:00 AM

■Functions Temporarily Unavailable

• New line activation for physical SIMs will not be available
• Activation codes for eSIMs will not be issued

■Notes

• Physical SIMs that request activation during the maintenance will be activated sequentially after the maintenance ends.
• Activation codes requested during the maintenance will be issued sequentially after the maintenance ends.
• SIM cards that have already been activated and are in use will not be affected.
• Activation codes that have already been issued can still be installed and used during the maintenance period.