When should I register my Japanese address?

Register at the responsible municipal office within 14 days after determining where you will live.

How much does National Health Insurance cover?

Official guidance says NHI generally covers 70% of eligible medical costs, leaving the insured person to pay 30%. Uncovered services are paid in full.

Do I need to declare income if I earned little or nothing?

Official guidance says income should still be declared so the municipality can calculate the premium correctly and determine any reduction.

Is My Number the same as the residence-card number?

No. My Number is a separate 12-digit social security and tax number assigned to residents.

Health Insurance, Residence Card & Ward Office Registration in Japan

A plain-language guide to residence cards, address registration, My Number, National Health Insurance, premiums and the procedures new students must not miss.

By SJLA Student Support Desk · Published 2026-08-03 · Updated 2026-08-03

Quick Answer

Students staying in Japan for more than three months generally receive a residence card and must register their address at the municipal office within 14 days after deciding where they live. After resident registration, eligible foreign residents enroll in National Health Insurance. My Number information is then issued through the resident-registration system.

Residence Card

The residence card records key immigration information such as name, status and period of stay. Official guidance says it should be carried at all times. Check the printed details immediately and ask the school or immigration office how to correct an error.

At major designated airports, the card may be issued during landing procedures. At some other entry points, the passport receives an indication and the card is mailed after address registration.

Municipal or Ward Office Registration

Confirm the address where you actually live.
Visit the city, ward, town or village office responsible for that address.
Bring the residence card; follow current instructions on any other documents.
Complete resident registration within the required period.
Ask about National Health Insurance, tax declarations, certificates and local services.

National Health Insurance

Official Study in Japan guidance says foreign residents staying three months or longer must enroll in National Health Insurance. Registration follows resident registration at the municipal office.

Topic	What students should know
Premium	Calculated using factors including previous-year income
Income declaration	Required for accurate premium and possible low-income reduction
Covered treatment	NHI generally covers 70% of eligible medical cost
Student payment	The patient generally pays the remaining 30%
Uncovered care	Some services must be paid in full

Rules and calculations depend on the municipality and case. Ask the local office for the current amount and reduction procedure.

My Number

My Number is a 12-digit social security and tax number issued to residents. It is different from the residence-card number. Keep the notification and card secure; do not send photos to unknown employers, agents or social-media contacts.

Common Mistakes

Missing the address-registration deadline
Moving without reporting the new address
Assuming “no income” means no income declaration is needed
Ignoring insurance notices written in Japanese
Lending the residence card or My Number
Letting passport, card and school records show inconsistent addresses

When You Move or Leave

Municipal and immigration notifications may be required when changing address, school, status or leaving Japan. Ask the school and the relevant office before the change, not afterward.

Official Sources

Residence card, resident registration and My Number: studyinjapan.go.jp/en/planning/immigration-procedures/
National Health Insurance coverage and premiums: studyinjapan.go.jp/en/life/insurance/
Status-of-residence guidance: studyinjapan.go.jp/en/life/residing-in-japan/