National Health Insurance problem

Hi everyone,

I was wondering if anyone here has advice or experience dealing with Japan’s National Health Insurance (国民健康保険税).

As far as I understand, in Japan when you’re enrolled either in 社会保険 (employee’s social insurance) or 国民健康保険 (National Health Insurance), your payments are calculated based on your previous year’s income.

Here’s my situation:

Until August this year, I was working full time as an ALT and was enrolled in Shakai Hoken through my job. My health insurance contribution was around ¥1,800 per month, which felt reasonable.

After my contract ended, I officially left Japan in August and later re-entered on a student visa last month as a full-time research student at a Japanese university (I become a graduate student from October next year).

However, when I registered at my new city hall, they told me that because I’m a "research student" and not a "full-degree graduate student", I must enroll in National Health Insurance instead of receiving any student exemption. I accepted this, assuming the cost would be around ¥8,000–10,000 per month.

Instead, I just received my new bill:
¥27,800 per month, calculated based on my previous ALT salary.

The problem is:
I am now a student with almost no income.
I spent most of my savings relocating to Tokyo, and my first part-time work payments won’t arrive until end of December.
Right now, it is literally a choice between paying my rent or paying National Health Insurance this month.

I don’t want to ignore it or get into legal trouble.
But realistically, this amount feels completely disconnected from my current life situation.

Does anyone here have experience with:

  • Transitioning from full-time work to a student visa?
  • Having NHI recalculated or reduced due to income changes?
  • Successfully negotiating with their local city hall for a payment reduction or postponement?

It just seems wild that when I was a working adult, my health insurance was ¥1,800/month, but now as a student with low income I’m suddenly expected to pay ¥27,800/month.

I’d really appreciate any advice, thank you in advance.

by Pretty-Ear8243