Be able to decide whether you need to join National Health Insurance, notify joining or leaving within the deadline, and understand how premiums and medical costs work.
Explanation
National Health Insurance (国民健康保険 / 国保) is a public medical insurance program run by municipalities. People who are registered as residents and are not covered by workplace health insurance or similar must join (people aged 75 or older are covered by the Late-Stage Elderly Medical Care System (後期高齢者医療制度) instead). Foreign nationals are covered if, for example, their period of stay is longer than 3 months. Short-term visitors such as tourists cannot join.
Notify your city/ward/town office where you live within 14 days from, for example, the day you registered as a resident or the day after you left your workplace health insurance. Even if you notify late, you must pay premiums retroactively from the time you should have joined.
Once enrolled, the medical costs you pay at the hospital counter are, as a rule, 30% (this differs by age and other factors), and if medical costs become high, the High-Cost Medical Expense Benefit system (高額療養費制度) caps what you pay. Use your My Number health insurance card (マイナ保険証) or eligibility certificate (資格確認書) when you see a doctor.
Premiums are set by the municipality based on factors such as income and household size, and are paid by the head of the household (世帯主). When you join workplace health insurance or leave Japan, you must notify the office to withdraw from National Health Insurance.
Foreign nationals whose period of stay is longer than 3 months and who are not covered by workplace health insurance or similar
People who came as tourists
Everyone, including people covered by workplace health insurance
Only Japanese nationals
AnswerA. Foreign nationals whose period of stay is longer than 3 months and who are not covered by workplace health insurance or similar
Foreign nationals join if their period of stay is longer than 3 months and they are not covered by workplace health insurance or similar (under age 75). Short-term visitors cannot join.
Q2
What is the deadline for notifying that you are joining?
Within 3 days
Within 14 days
Within 3 months
Within 1 year
AnswerB. Within 14 days
Within 14 days from, for example, the day you registered as a resident or the day after you left your workplace insurance.
Q3
Once enrolled, how much of your medical costs do you pay at the hospital counter, as a rule?
Nothing
The full amount
50%
30%, as a rule
AnswerD. 30%, as a rule
As a rule, 30%. The percentage is different for children who have not yet started elementary school, people aged 70 or older, and others.
Q4
What happens to your premiums if you notify late?
They are waived
Nothing changes
You pay them retroactively from the time you should have joined
They are cut in half
AnswerC. You pay them retroactively from the time you should have joined
Even if you are late, you pay the premiums retroactively. Notify as early as possible.
Q5
If you join your company's health insurance, what happens to National Health Insurance?
You leave it automatically
Notify within 14 days that you are leaving National Health Insurance
You keep paying premiums for both
You do not need to do anything
AnswerB. Notify within 14 days that you are leaving National Health Insurance
You do not leave National Health Insurance automatically. Take something showing your workplace insurance coverage to the office and notify them.
Frequently asked questions
Q. What if I cannot pay the premiums?
A. Do not leave it; talk to your municipal office as soon as possible. There are systems that reduce premiums for low-income households, and you may be able to receive a reduction or exemption if you have special circumstances. If you keep failing to pay, measures may be taken, such as requiring you to pay the full medical cost at first. In addition, the national government plans to start a system from June 2027 that checks information on foreign nationals' unpaid premiums in reviews such as renewals of the period of stay (please check future announcements for details).
Q. What if my medical costs become high?
A. If your out-of-pocket medical costs in one month exceed the upper limit, the excess amount is paid to you as a "High-Cost Medical Expense Benefit" (高額療養費). The upper limit differs by age and income. If you use your My Number health insurance card, the amount you pay at the counter for insured care is capped at the upper limit even without an advance procedure (a Certificate of Ceiling-Amount Application / 限度額適用認定証) (meals during hospitalization, extra charges for private rooms, and similar costs are not covered). For details, check with your municipal office.
Q. Do international students also join?
A. People with the status of residence "Student" (留学) also join if they live in Japan for more than 3 months and are not covered by other health insurance. It is a good idea to complete the procedure at the same time as your resident registration.
Practice: answer the questions on this page
This practice tool asks questions in random order (it works when JavaScript is enabled). You can still read all the questions and explanations above without it.
Systems and procedures may differ depending on the city, ward, town or village where you live and on the time of year. Please check the latest information from your local government or the relevant organizations. Content checked on: 2026-09-28
This page is a translation of the Japanese original. If the translation and the original differ, the Japanese version takes precedence. View the Japanese original