National health insurance in Japan and what it costs

Who has to join national health insurance

Anyone living in Japan who is not on an employer's health insurance, including students, part-timers and the self-employed (Nakano-ku). You register at the ward or city office within 14 days of the day your other cover ended, and the membership is backdated to that day, not to the day you turn up. Waiting does not save money; it only means more bills arrive at once.

Bring your residence card and the certificate your employer's insurer issues when you leave (健康保険資格喪失証明書). The same counter handles the move-in paperwork on our moving in page.

Once you are enrolled, see how to find a doctor who speaks your language.

What national health insurance costs by income

The table shows one person aged 30, by last year's salary. Chiyoda uses the standard special-ward rates, which most wards share; Nakano and Edogawa are the two wards whose 2026 rates differ at that age. The selector above covers all 23 wards and four other cities. The figure is the whole year; the bills arrive in 10 installments from June.

Ages 40 to 64 add the long-term care part, which is roughly a quarter more. Meguro differs from the standard rates only in the long-term-care rate for ages 40 to 64. Rates are for fiscal 2026 (令和8年度), in force from April 2026 to March 2027.

How much does national health insurance differ between Tokyo, Osaka, Yokohama, Nagoya and Fukuoka?

On the same ¥4,000,000 salary at age 30 it runs from ¥270,200 a year in Fukuoka City to ¥391,947 in Osaka City, because each city sets its own rates every April. The table uses one person aged 30 and Chiyoda-ku for the standard Tokyo schedule.

Osaka and Fukuoka add a charge per household (平等割) to the per-person charge; Tokyo's wards, Yokohama and Nagoya have none. Osaka's medical cap is ¥660,000, against ¥670,000 in the others. Nagoya takes ¥2,000 a person off the per-person part of a household that gets the low-income cut (Nagoya City). Osaka Prefecture charges one rate everywhere in the prefecture (Osaka City), so the Osaka column also holds for Sakai, Suita and the rest of the prefecture. Each city rounds its own way, so a bill can differ from the table by a few yen.

How much is national health insurance in your first year in Japan?

Often very little. The income-based part is charged on the previous calendar year's income (Nakano-ku), so someone who arrived this year with no income in Japan last year is charged on zero. The per-person part is then cut by 70%, which in Nakano-ku leaves ¥19,912 for a full year. You owe it from the month you became eligible, not the month you registered (Nakano-ku), so a part year costs less. Fukuoka spells the rule out: the year's premium times the months you were enrolled, divided by 12 (Fukuoka City).

The jump comes in the April after your first full calendar year of Japanese pay, because that year then becomes the previous year. Here is someone who arrives in October 2026 on ¥300,000 a month, in Nakano-ku, at 2026 rates:

Rates change every April, so the last two rows are estimates, not quotes. Resident tax follows the same one-year lag; the take-home pay calculator shows that side of it.

People who move in from abroad get a form from the ward, the national health insurance declaration (国民健康保険に関する申告書), and must return it (Nakano-ku). Return it even if you earned nothing. The low-income cut applies only when the ward knows the income of everyone in the household (Nakano-ku), and Fukuoka says a household with a member whose income is unknown gets no cut (Fukuoka City). The city pages we read do not say whether income earned abroad counts, so ask at the counter if you had some.

After you leave a job: national health insurance or voluntary continuation

Two common options are national health insurance and voluntary continuation (任意継続); dependent cover under a family member's employer plan may be a separate option if you qualify. The voluntary continuation application has a 20-day deadline. Either you join the national health insurance at your ward office, or you stay on your employer's insurer as a voluntarily continued member (任意継続被保険者) for up to two years (Japan Health Insurance Association (協会けんぽ)).

On voluntary continuation you pay the whole premium instead of half, because the company's share stops (Japan Health Insurance Association (協会けんぽ)), but it is worked out on a pay grade of at most ¥320,000. That cap is why it often wins for someone who was paid well last year: the national premium follows last year's income with no such ceiling until the category caps. The calculator above compares the two on your own figures.

Two things the comparison does not decide for you. Voluntary continuation keeps dependents covered, which the national insurance has no equivalent of: everyone is charged separately. And if you lost the job involuntarily, the ward can charge your national premium as though your salary were 30% of what it was, which usually makes it the cheaper side. Ask at the counter with your unemployment benefit eligibility certificate (雇用保険受給資格者証).

The pension bill that comes with it

Leaving employment also moves you onto the National Pension, a flat ¥17,920 a month for fiscal 2026 (令和8年度) (Japan Pension Service), whatever you earn. Students can apply for the student payment exception and low earners for a full or partial exemption, both at the same counter. That is a separate bill from the health insurance, and this calculator does not include it.

What this calculator leaves out

• Every municipality except Tokyo's 23 special wards and the cities of Osaka, Yokohama, Nagoya and Fukuoka. Rates differ by municipality.
• Local reductions that need dependents or a disability: Nagoya's income-based deduction and Yokohama's reduction for households with children.
• Households with more than one person. Each member adds a per-person part, and the income of everyone in the household counts toward the reduction.
• The reduction for involuntary job loss, which the ward has to certify.
• People aged 75 and over, who move to a separate system (後期高齢者医療制度).
• Company health insurance societies (組合健保), whose voluntary continuation rates are their own.
• Exemption during pregnancy and after birth, and any local hardship reduction.
• How your own ward splits the year into bills. The calculator rounds each bill down to ¥10 and adds the rest to June, as Shibuya-ku shows it; another ward's bills can differ by a few yen. For Osaka, Yokohama, Nagoya and Fukuoka it shows the year's total only.

Health insurance is one line in a month. The rest of them are on the cost of living calculator.