Employee Health Insurance vs NHI in Japan

Last updated: 17 October 2026 · Kyokai Kenpo’s rates for fiscal 2026 · the National Health Insurance Act

Almost everybody living in Japan is in a public health insurance scheme, and for most working people it is one of two. A salaried employee is in employee health insurance (健康保険): the Japan Health Insurance Association (協会けんぽ, Kyokai Kenpo), or a company’s own health insurance society (健康保険組合). Everybody else under 75 — the self-employed, freelancers, people between jobs, many part-timers — is in National Health Insurance (国民健康保険, kokumin kenkō hoken, often shortened to NHI), run by the city. Treatment is the same in both. What differs is how the premium is set, whether your family is covered, and whether you are paid while off sick. The difference matters most the week you leave a job, when you have three choices and short deadlines.

This is a general explanation. Rates for company societies, and every National Health Insurance premium, are set locally: your society or your city office has the figure for you.

The two side by side

How each premium is worked out

Employee health insurance is a percentage of your insurance grade (標準報酬月額), the band your monthly pay falls in. For Kyokai Kenpo in Tokyo in fiscal 2026 it is 9.85%, plus a 0.23% child-care support levy, so 10.08% in all, and your employer pays half of it. From 40 to 64 the long-term care premium is added on top, 1.62% nationwide, again half each. A company society sets its own rate, often lower. The calculator on this site works the premium out from your salary.

National Health Insurance has no employer half and no grade. Your city charges the household, adding up an income-based part — mostly worked out on the previous calendar year’s income — and flat amounts for each member and, in many cities, for the household. Each city sets its own rates and an annual ceiling, so the same income can cost noticeably different amounts a few stations apart. Low-income households have the flat parts reduced by law. Two things follow for people from abroad: in your first year in Japan there may be little Japanese income from the year before, so the premium can be low; and in the year after a well-paid job ends, it can be high, because it is charged on the salary you no longer have.

Your family

Employee health insurance covers your dependents (被扶養者) — a spouse, children, parents and some other relatives you support — and charges nothing extra for them. A relative counts as a dependent when their income is under ¥1,300,000 a year (¥1,800,000 if they are 60 or over or have a qualifying disability, and ¥1,500,000 for a relative aged 19 to 22 on 31 December of that year who is not your spouse) and, if they live with you, under half of yours; if they live apart, it has to be less than what you send them. Only a spouse, children, grandchildren, brothers and sisters, parents and grandparents can be dependents while living apart; other relatives — an uncle, a niece, a parent-in-law — have to live in your household. Income here means what they expect to receive over the year from the day they become your dependent — salary, pensions and benefits included — not what they earned before. Unemployment benefit counts as income here, as a daily amount: under the ¥1,300,000 limit a relative receiving it qualifies only at ¥3,611 a day or less, and the higher limits allow proportionately more. A dependent normally has to live in Japan. Your employer reports a new dependent, within 5 days.

National Health Insurance has no dependents. A spouse and two children on it are three members, each adding a flat amount to the household’s premium. That one difference is often what decides the choice after a job ends.

When you are ill or having a baby

Employee health insurance pays a sickness allowance (傷病手当金) of about two-thirds of your insurance grade while you cannot work, and a maternity allowance (出産手当金) around the birth. National Health Insurance does not have to: the law lets a city pay a sickness allowance but does not require one. The guide to sick leave pay has the details, including when the allowance carries on after you leave a job. Both schemes pay the childbirth lump sum and the same share of your medical bills.

When you leave a job: the three choices

Your employee coverage ends the day after your employment end date (退職日), which is later than your last day at work if you use up paid leave first. Unless a new employer’s insurance starts the next day, you need one of these three, and two of them have deadlines measured in days.

1. Keep your employee insurance: voluntary continuation (任意継続)

• Who can: anyone who was in employee health insurance for at least 2 months without a break up to leaving. The months can be with more than one employer, as long as there was no gap.
• Deadline: apply to Kyokai Kenpo (or your society) within 20 days of the day your coverage ended — the next working day if the 20th is a weekend or holiday. A form sent by post has to arrive in time.
• How long: up to 2 years. It ends earlier if you join a new employer’s insurance, miss a payment, or ask to leave.
• What it costs: both halves of the premium, since there is no employer any more — at the rate of the prefecture you live in. Kyokai Kenpo caps the grade it is charged on at ¥320,000 for fiscal 2026.
• What you lose: no sickness or maternity allowance for anything that starts after you leave. Your dependents stay covered, at no extra cost.

In Tokyo, somebody on a ¥300,000 grade paid ¥15,120 a month while employed and pays ¥30,240 on voluntary continuation. On a ¥500,000 grade the payslip took ¥25,200, and voluntary continuation charges ¥32,256 — the capped grade times 10.08% — rather than the ¥50,400 the full grade would come to. The cap is what makes this option good value for people who were well paid.

2. Join National Health Insurance at your city office

• Deadline: the head of the household registers you within 14 days of losing employee insurance, at the city or ward office, usually with proof of the date it ended.
• From when: the law makes you a member from the day your employee coverage ended, whenever you register. Registering late does not save the premium for those weeks; it only leaves you paying your medical bills in full until the paperwork catches up.
• If you lost the job involuntarily: if Hello Work classes you as laid off or as leaving for a reason it accepts (特定受給資格者・特定理由離職者), your employment income from the previous year — salary after the employment income deduction (給与所得), not the gross figure — is counted at 30% when the premium is worked out, from the day after your employment ends until the end of the following fiscal year — the year after the April-to-March year that day falls in. Employment ending on 31 March 2026 is covered until March 2028. Take your unemployment insurance papers when you register.

3. Become a dependent on a family member’s employee insurance

If your spouse, or another family member who can count you as a dependent (above), is in employee health insurance and your income is under the limits above, you can be added as their dependent and pay nothing. What counts is the income you expect from now on, so a salary you earned before leaving does not rule you out. Their employer files it. Unemployment benefit counts: under the ¥1,300,000 limit, while you receive more than ¥3,611 a day you are not a dependent (the higher limits allow more), though you can be during the waiting period before it starts.

Which one

• Ask both prices. Kyokai Kenpo will tell you the voluntary continuation premium; your city office can estimate National Health Insurance from your previous year’s income. You have 20 days to decide.
• Voluntary continuation tends to win for somebody who was well paid (the grade cap), or who has a spouse or children who would otherwise each be charged on National Health Insurance.
• National Health Insurance tends to win after an involuntary job loss, because of the 30% rule, and in the second year after leaving, when the year it is charged on has little salary in it.
• A family member’s insurance wins whenever you qualify, because it is free.

Leaving a job takes you out of the employees’ pension too. If you live in Japan and are 20 to 59, you then register for the National Pension at the city office and pay it yourself — unless you qualify as the dependent spouse of somebody in the employees’ pension (国民年金第3号被保険者). That has conditions of its own, separate from health insurance: being your spouse’s health insurance dependent is not enough if, for example, your spouse is 65 or over and entitled to an old-age pension. If you are leaving Japan altogether, the guide to leaving Japan covers that instead.

Questions people ask

Can I choose National Health Insurance instead of my company’s insurance?

No. If your job puts you in employee health insurance, you are in it, and the law keeps anyone covered by it — or covered as a dependent — out of National Health Insurance. The choice only opens up when that coverage ends.

I missed the 20-day deadline for voluntary continuation. What now?

Then the choice is National Health Insurance at your city office, or a family member’s employee insurance as a dependent if you qualify. National Health Insurance starts from the day your old coverage ended, whenever you register, so register within 14 days rather than waiting.

Can I leave voluntary continuation early?

Yes. It ends on its own when you join a new employer’s insurance or miss a payment, and Kyokai Kenpo also lists asking to leave as a way to end it. Join National Health Insurance or a family member’s insurance from the day it ends, so there is no gap.

See the premium on your salary

Sources

• Japan Health Insurance Association — 令和8年度 都道府県単位保険料率 (Tokyo 9.85%, the child-care support levy 0.23%, long-term care 1.62%). Japanese.
• Japan Health Insurance Association — 任意継続被保険者となるための要件 (2 months, 20 days, 2 years; twice the premium deducted before, at the rate of the prefecture you live in; the ¥320,000 grade cap; no sickness or maternity allowance for anything arising during it; the ways it ends, including asking to leave) and 任意継続の加入条件について (the 2 months may span employers without a gap; the 20th day moves to the next working day; coverage ends the day after the employment end date, 退職日の翌日). Japanese, opened 17 October 2026.
• Japan Health Insurance Association — 任意継続 (a grade above ¥320,000 is charged as ¥320,000; the premium may not be exactly twice when you live in a different prefecture from your old branch). Japanese, opened 17 October 2026.
• Japan Pension Service — 従業員が家族を被扶養者にするとき (who may live apart and who must share your household; the income limits, counted on expected income from the day of recognition rather than past income, ¥1,500,000 for ages 19 to 22 from 1 October 2025, half of your income or less than you send, unemployment benefit and other allowances counted, ¥3,611 a day under the ¥1,300,000 limit, living in Japan, 5 days). Japanese, updated 30 September 2026, opened 17 October 2026.
• Ministry of Health, Labour and Welfare — 国民健康保険の保険料・保険税について (charged by household, set by each city’s ordinance, statutory reductions of the flat parts, and the 30% rule for involuntary job loss, applied to 給与所得 until the end of the fiscal year after the one containing the day after separation). Japanese, opened 17 October 2026.
• National Health Insurance Act (国民健康保険法) — e-Gov: 第6条 (people in employee health insurance, and their dependents, are not members), 第7条 (membership from the day that coverage ends) and 第58条第2項 (a city may pay a sickness allowance); and its Enforcement Regulations (国民健康保険法施行規則) — e-Gov: 第3条 (the head of household registers within 14 days). Japanese, opened 17 October 2026.
• Japan Pension Service — 国民年金の加入手続き (residents aged 20 to 59 outside the employees’ pension join the National Pension; the conditions for a dependent spouse, 第3号被保険者, including the exclusion of a spouse aged 65 to 69 entitled to an old-age pension). Japanese, updated 11 September 2025, opened 17 October 2026.