Salary Deductions in Japan: the Surprise Isn’t on the First Payslip

There’s an evergreen genre of articles: “the shock of my first Japanese payslip.” The salary in your contract and the number that lands in your bank account are indeed far apart — tax, pension, health insurance, all queueing up to take their cut first.

My story is a little different, and that’s exactly why it might be useful: my first payslip didn’t surprise me at all. The surprise came a year later, from a direction I didn’t expect.

Why the First Payslip Held No Shock

Simple: I had already been shocked, years earlier.

As a NIMS Junior Researcher during the PhD, I was paid like an employee — complete with tax deductions and all their friends. Every ounce of “why is the number this much smaller” surprise had already been spent during my student years.

So when the first SOLIZE payslip arrived in April 2025, it read as familiar. That first salary also had a job waiting before it even arrived: covering the March moving-out costs and re-stabilizing the household economy after leaving Tsukuba.

If you’re on the salaried-PhD path in Japan, this is a hidden bonus nobody mentions: you graduate already trained to read a Japanese payslip.

The Real Surprise: After the Raise

In February 2026, my base salary went up. Happy news — until April 2026, when the payslip showed the other side of the raise.

My total monthly deductions (tax + pension + insurance) jumped from about ¥50,000 to almost ¥70,000.

What happened: pension and insurance deductions in Japan aren’t computed from thin air — they follow a grade determined by your salary level. Get a big enough raise, and your projected annual income climbs a bracket; your deductions climb with it. A raise is still a raise — but part of it is reclaimed by the system before you ever feel it.

The Lesson: Celebrate a Raise One Payslip Late

• Never budget 100% of your raise. Some of it will be taken back through deductions that readjust a few months later.
• When the raise is announced, wait for the payslip after the deduction adjustment before changing your lifestyle — that net figure is your real raise.
• And if you come from a salaried research position: appreciate your five years of “payslip training.” It’s financial literacy other people pay for in shock.

Check the Current Rules

Tax rates, pension premiums, and health-insurance rates are revised regularly, and the grade-adjustment mechanics have details I haven’t covered here. For financial decisions, verify against your own payslip and the official sources. The figures in this article are purely personal experience, 2025–2026.