Before you start

Ward registration completed
Residence card
Employment details, if enrolling through an employer scheme
My Number

Step-by-step

1
Establish which scheme you are in
Full-time employees are usually enrolled in shakai hoken by their employer, which splits contributions and includes pension. Everyone else — freelancers, part-timers, students, people between jobs — must enrol in National Health Insurance at the ward office themselves. There is no third option of being uninsured.
Via employerWho: YouWeek 1–2
2
Enrol at the ward office if your employer does not
Do it in the same visit as your address registration. National Health Insurance premiums are income-based and calculated on last year's income, so a first year in Japan is usually very cheap and the second is not.
In personWho: YouWithin 14 days
3
Understand the 30% co-payment and the monthly ceiling
You pay 30% of most treatment costs at the counter. Above a monthly threshold that scales with income, the high-cost medical expense benefit caps what you pay. Apply for a limit certificate in advance if you know a major treatment is coming.
In personWho: You
4
Enrol in the pension and keep every record
Pension enrolment is compulsory alongside health insurance. Keep your pension book and all contribution records — they are what you need to claim the lump-sum withdrawal if you leave Japan.
In personWho: You
5
Register your My Number card as your insurance card
Japan has moved to using the My Number card as the health insurance card. Registering it means treatment history and prescriptions are visible to providers with your consent, and it simplifies claiming the high-cost benefit.
OnlineWho: You
6
Claim the pension lump-sum withdrawal when you leave
If you leave Japan having contributed for at least six months, you can claim a lump-sum refund of part of your pension contributions, applied for within two years of departure. It is very commonly forgotten.
OnlineWho: YouWithin 2 years of leaving Japan

Documents you’ll need

Residence card
My Number
Health insurance card or registered My Number card
Pension handbook
Jūminhyō residence certificate

Things most newcomers don’t know

The high-cost medical expense benefit is what makes the 30% co-payment survivable.

Paying 30% of everything sounds alarming until you learn that monthly out-of-pocket costs are capped at a threshold scaling with income. A major operation or a long hospital stay costs a manageable amount rather than a catastrophic one. Applying for the limit certificate before a planned treatment means the cap is applied at the counter.

Source: Ministry of Health, Labour and Welfare

The pension lump-sum withdrawal is real money and departing residents routinely forget it.

Anyone who contributed for at least six months can claim back part of their pension contributions after leaving Japan, applied for within two years of departure. It requires paperwork sent from abroad plus a Japanese bank account or a tax representative, so the groundwork has to be done before you go.

Source: Japan Pension Service

National Health Insurance premiums are based on last year's income, so year two is the expensive one.

Your first year in Japan is assessed on a Japanese income of zero, which makes premiums minimal and gives a badly misleading impression of the cost. From the second year they are calculated on your actual earnings and rise sharply, in the same way residence tax does.

Source: Saitama City

Specialist care is closer than a commuter city usually manages, because the prefecture put its hospitals together.

Saitama Prefecture clustered several flagship institutions — the Red Cross hospital, the Children's Medical Center and the Cardiovascular and Respiratory Center among them — around Saitama-Shintoshin rather than dispersing them. For a household that would otherwise assume anything serious means a trip into Tokyo, that is a meaningful difference, and it is worth knowing which of your local hospitals holds emergency designation before you need one.

Source: Saitama City

Common mistakes to avoid

Assuming health insurance is optional if you are self-employed — it is not.
Budgeting from your artificially low first-year premium.
Leaving Japan without claiming the pension lump-sum withdrawal.
Not applying for a limit certificate before a planned major treatment.
Assuming serious treatment means travelling into Tokyo when the prefecture's flagship hospitals are three stops away.

Some of this may be out of date. Spotted something inaccurate? Help us keep it right for the next newcomer.