My Number Card in Japan: What It Is and Why Residents Use It

Understand the difference between your 12-digit My Number and the My Number Card, what the card is used for, and how foreign residents apply and keep it valid.

Published October 20, 2026 at 11:04 AM JST | By Tokyo Paul

Quick answer: My Number is a 12-digit individual number given to everyone with a resident record in Japan. The My Number Card is an optional plastic IC card with your photo that works as photo ID, can be used to obtain certificates, and can serve as your health insurance card once registered. Foreign residents can apply, and the card's validity follows the period of stay.

My Number and the card are different

The My Number is a 12-digit individual number assigned to each person who has a resident record in Japan, regardless of nationality. It is used for social security, tax and disaster-response procedures, and the number itself does not contain details such as your address or date of birth. After resident registration at a municipal office, new arrivals are mailed a notification card showing their number, sent to the address on the resident record.

The My Number Card is something else. It is a plastic IC card with your name, address, date of birth, sex and photo on the front, and your number on the back. Applying for it is voluntary, and the first application is free. The notification card carries no photograph, so many residents apply for the card to have one document that serves several purposes: proof of who you are, a way to reach official services, and a health insurance card.

New residents receive the number after they register their address at the municipal office. Keep the notification card safe, since the number may be requested by an employer or for other formal procedures, and treat it as private information.

Everyday uses

The card works as proof of identity and address anywhere that accepts official ID. It can be used to obtain certificates such as a residence record or a seal registration certificate at convenience store multi-copy machines, which saves a trip to the municipal office during working hours. Employers may also ask for proof of your number, and the card satisfies that requirement together with its photo identification.

The card is an IC card, and PIN codes protect it, so it can also be used for secure online procedures on government portals. Which services are available depends on your municipality and on what you register, so check your local office's page and the Digital Agency site.

Using the card as a health insurance card

The most visible change in recent years is that the card can serve as your health insurance certificate. According to the Digital Agency, existing health insurance cards were no longer available on and after 2 December 2025, and a registered My Number Card is now the main way to show your insurance. You only need to register for the first time, and then you use the card at clinics, hospitals and pharmacies that have card readers.

At the reader you insert the card, verify your identity with face recognition or a four-digit PIN, choose whether to share information such as past medication, and take the card back to complete check-in. Information you have not agreed to is not provided to doctors and pharmacists. If you do not have a registered card, your insurer issues a free Eligibility Confirmation Form instead.

Who can apply, including foreign residents

Residents with a resident record can apply, whatever their nationality. For foreign residents, the card's validity ends when the period of stay ends, unless the person is a permanent or special permanent resident. If you extend your stay, visit your municipal office before the current period expires to extend the card's validity too. The card is not updated automatically when your period of stay changes.

If your status is about to change, such as moving from a student status to a work status, official guidance suggests it may be easier to apply after the change is made. Policies for people with unusual circumstances, such as short stays, differ, so ask about your own case. Municipal offices can answer questions in person, and the official card site has described a call center for inquiries in several languages, so check the current languages and hours.

How to apply

You can apply by mail, online or through a smartphone, depending on your municipality. A portrait photograph is attached to or uploaded with the application, and the application form ID must be entered correctly or the card cannot be issued. After processing, a notice is mailed saying the card is ready.

You then make an appointment, usually by phone or an online reservation system, and collect the card in person at the municipal office. Bring the items listed in the notice, which for foreign residents usually include a residence card and may include the notification card. Allow some time for the appointment, because staff check your identity and guide you through setting PINs. At the counter you set your PIN codes. Procedures differ by city, so follow the instructions from your own municipality.

Keeping the card valid

Update your information when anything changes. Changes of name or address are reported at the municipal office, usually with the card, soon after they happen, so ask the office which deadline applies. Foreign residents should also keep the expiry in mind and renew the card's validity when extending the period of stay.

If the card is lost or stolen, you can suspend it by calling the toll-free call center number listed on the official card site, in an emergency. Then contact your municipal office and the police, and ask about reissue. Keep your PINs private and do not share your number unnecessarily, because it is meant for specific official purposes. At a clinic reader you take your card back after check-in, and the Digital Agency notes that information you have not agreed to will not be provided.

Practical tips for new residents

Apply early if you plan to stay in Japan for some time, since the card makes many procedures easier and is now part of how health insurance works. Keep your notification card in a safe place until you have the card. If you hold a registered card, make a habit of bringing it to the clinic along with any other ID your provider asks for.

Some people choose not to apply, and the notification card plus other ID remains workable for many purposes. This guide shares general information; rules change, so confirm details with the official agency or provider before you act. Municipal websites, the Digital Agency and the Ministry of Internal Affairs and Communications publish current instructions, often in English.

Frequently Asked Questions

Is the My Number Card mandatory?

No. Applying for the card is voluntary and the first issue is free. Everyone with a resident record has a My Number, but the card is optional. Many residents apply because it works as photo ID and as a health insurance card.

Can foreign residents get a My Number Card?

Yes. Foreign residents with a resident record can apply. The card's validity ends when the period of stay ends, except for permanent residents, so extend it at your municipal office when you extend your stay.

How do I use it at a clinic?

Register the card for health insurance use first, using the online portal, an ATM or a clinic reader. At the clinic, insert the card into the reader, confirm your identity with face recognition or PIN, and retrieve the card. If you have not registered, use the Eligibility Confirmation Form from your insurer.

Want to go deeper? Tokyo Paul's book Building a Life in Japan is available on Amazon.

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