Social Security and Tax Number (My Number)

What is a Social Security and Tax Number (“My Number”)?

A Social Security and Tax Number (SSTN, also called “My Number”) is an important 12-digit number for the appropriate and efficient management of personal information used for tax, social security, and in relation to disaster prevention measures, that is allocated to each and every individual (including foreign nationals) with a certificate of residence within Japan to be used throughout one’s whole life. In principle, the number shall not change unless it has been compromised and there are concerns of fraudulent use.

Please refer here for the details.

My Number Notice

A “My Number Notice” (kojin bango tsuuchisho/個人番号通知書）containing their full name, date of birth, and Individual Number (My Number) will be issued to international students and researchers who are registered as residents in Japan. This notice will be sent to the residential addresses of international students and researchers approximately 2-3 weeks after the completion of residence registration.

Please note that the My Number Notice will be sent by simplified registered mail, so you must be present in order to receive it. In the event of your absence, you will receive a delivery notice with instructions on redelivery. Please make sure to receive it within the storage period.

The My Number Notice contains the following :

  • QR Code (for online application)
  • Application Form and Return Envelope (for application through postal mail)
  • Instruction Booklet

Follow the instruction in the booklet to apply for a My Number Card online or by postal mail.

Please refer to this website for the details.

My Number Notice
My Number Application Form
Return Envelope for Mail Application
Instruction Booklet

Provision of SSTN

Businesses such as companies are required to record SSTN on various applications and reports prescribed by law and provide them to relevant institutions. As a business, Tohoku University is also required to seek information about SSTN, including dependent family members, from staff and relevant students engaged as TA, RA, etc.
Furthermore, since collecting and providing such information is prohibited other than for procedures prescribed by law, your SSTN should not be provided to others indiscriminately. Please take care concerning suspicious telephone calls, emails, letters and visits, etc. concerning the SSTN System.

Other SSTN Notification Card Procedures

When you move

When you move and report your address change to your municipality or city ward office, please bring your Notification Card and go through the procedure to change the former address on your Notification Card to the new address.

When you leave Japan

Please refer to Leaving Japan

References

SSTN Website

The Use of My Number Card as Health Insurance Card

Starting December 2, 2024, new National Health Insurance cards will no longer be issued. Instead, the system will transition to using My Number Cards as health insurance cards. However, your current health insurance card will remain valid until its expiration date, up to a maximum of one year.

To use your My Number Card as a health insurance card, prior registration is required through the Mynaportal website or at Seven Bank ATMs.

For individuals enrolled in National Health Insurance:

  • If there are no changes to your enrollment status, you can continue using your current health insurance card until September 30, 2025. However, if your address or name changes, your card will no longer be valid, even before this date. In such cases, a “Notice of Credentials” or an “Eligibility Verification Card” will be issued.
  • Those who do not have a My Number Insurance Card will automatically receive an “Eligibility Verification Card” annually before their current one expires (July 31). The new card will be valid for one year from August 1 to July 31. By presenting this card at medical institutions, you can continue receiving treatment as before.

For TU employees enrolled in the MEXT Mutual Aid Association (MAA):

  • If there are no changes to your enrollment status, you can continue using your current MEXT MAA insurance card until December 1, 2025.
  • Employees who hold a My Number Card will receive a “Notice of Credentials” slip. Those who do not use their My Number Card as a health insurance card will be issued an “Eligibility Verification Card.”

For more information, please refer to the following links:

SNS

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