This is an English translation of our Japanese article. Rules and rates change every fiscal year; the Japanese version and the official materials of the Japan Health Insurance Association and your municipality are authoritative.
Japan Health Insurance After Leaving a Job: Voluntary Continuation vs National Health Insurance
After you leave a job in Japan, choosing voluntary continuation (nin-i keizoku) or National Health Insurance (kokumin kenko hoken) can change your annual cost by tens of thousands to hundreds of thousands of yen. And the better choice usually flips between year 1 and year 2. Enter your final monthly salary, last year’s income and your municipality to compare two full years.
Everything is calculated on your device and nothing is sent anywhere. Figures are estimates.
How to read the result: the answer changes in year 2
The two systems set premiums in completely different ways.
| Voluntary continuation | National Health Insurance | |
|---|---|---|
| Basis | Standard monthly remuneration at retirement (capped) | Last year’s income |
| Year 2 | Essentially unchanged | Falls sharply as last year’s income drops |
| Dependants | Covered at no extra cost | A per-capita levy for each person |
| Involuntary leaving | No effect | Income-based portion drops sharply |
So people with dependants tend to do better on voluntary continuation, while year 2 usually favours National Health Insurance. That is why "voluntary continuation in year 1, then switch" is often the cheapest combination.
Since January 2022 you may leave voluntary continuation early. A change to the Health Insurance Act allows withdrawal on the insured person’s own application, so using it for one year and moving to National Health Insurance is now clearly possible.
How the voluntary continuation premium is set
Premium (Kyokai Kenpo, FY2026)
Standard monthly remuneration × (prefectural rate + child-care support 0.23% + long-term care 1.62%*)
*Long-term care applies only to ages 40–64. The standard monthly remuneration is the lower of your figure at retirement and the association average; the FY2026 cap is 320,000 yen.
While employed your employer paid half. Under voluntary continuation you pay all of it — roughly double the health insurance line on your payslip. Applications must be filed within 20 days of losing your insured status.
How National Health Insurance is set
Basic structure
(Last year’s total income − 430,000 yen) × rate + per-capita levy × people + per-household levy
Rates are set by each municipality, so the same income can differ by more than 100,000 yen a year depending on where you live.
Involuntary leaving cuts the income-based portion
If you left through bankruptcy, dismissal or non-renewal (a specified recipient or specified reason leaver under employment insurance, under 65), your employment income is treated as 30% of the actual figure. It applies from the month after your leaving date until the end of the following fiscal year — up to about two years. You must apply at your municipal office; it is not automatic.
If you can join a family member’s insurance, that is cheapest
There is a third option. Becoming a dependant on a family member’s employee health insurance costs nothing. The usual condition is annual income under 1.3 million yen (1.8 million if 60 or over) and less than half the insured person’s income. Note that unemployment benefit counts as income: while receiving 3,612 yen or more a day you generally cannot be a dependant.
FAQ
Which is actually cheaper?
It depends. People with dependants often do better on voluntary continuation, while a single person in year 2 usually does better on National Health Insurance. If you left involuntarily, the income-based portion drops to about 30%, so National Health Insurance can win from year 1.
Does the voluntary continuation premium fall in year 2?
No. It is fixed on your standard monthly remuneration at retirement (capped at 320,000 yen). Only a change in the prefectural rate moves it. This is the biggest difference from National Health Insurance.
Can I use voluntary continuation for one year then switch?
Yes. Since January 2022 you may withdraw on your own application. Your status ends on the last day of the month in which the application is accepted, and you join National Health Insurance from the next day.
I missed the 20-day deadline.
Voluntary continuation is then generally unavailable, leaving National Health Insurance or a family member’s cover. The 20-day limit from loss of insured status is applied strictly.
Can I be a dependant while receiving unemployment benefit?
If the daily basic allowance is 3,612 yen or more, you generally cannot, because annual income is projected above 1.3 million yen. Treatment varies by insurer, so always confirm with them.