Everyone remembers to cancel the phone and the apartment. Almost no one thinks about the income tax return for the year they leave. Mio doesn't leave loose ends — a mid-year exit changes how (and when) your income tax gets settled. Here's the calm version.
If you're a regular employee, your company usually reconciles your income tax through year-end adjustment (nenmatsu chōsei) in December — it trues up the tax withheld each month against your full-year figure, and most people never file anything themselves.
But that mechanism assumes you're still employed at year-end. If you leave Japan part-way through the year and lose your domicile and residence for tax purposes, the December adjustment may never happen for you — so the tax on your final-year income isn't automatically squared up. You could have over-paid (a refund you'd never claim) or under-paid (a balance you still owe). Either way, the responsibility to file a final income tax return falls to you.
The NTA is explicit: if you leave Japan without designating a tax agent, you must file a final return and pay the tax before your departure. Because it covers only the part-year up to your exit, this is often called a quasi-final return (jun-kakutei shinkoku).
You file it at the tax office with jurisdiction over your Japanese domicile or residence, and pay before you go. It's clean — nothing follows you overseas — but it's under time pressure right when you're packing, and if a refund can't be finalised yet, chasing it later can be awkward.
The alternative: before you leave, submit a "Notification of Tax Agent" and appoint a nōzei kanrinin — a person who resides in Japan, or a Japanese corporation (a trusted friend, your employer, or a tax accountant). Per the NTA, if you submit that notification before departure, you (through your agent) file the return and pay the tax between February 16 and March 15 of the following year — the normal filing window.
This buys you time and a local hand to receive documents and settle the balance or receive a refund on your behalf. The catch: the notification generally must be filed before you depart — you can't conveniently set this up once you've already left. The tax office is determined by your place for tax payment, not the agent's address.
A mid-year departure can cut either way. If you'd earned less for the year than your monthly withholding assumed (withholding is calculated as if your monthly pay continued all year), you may be due a refund — a real reason to file. If you had extra income the payroll didn't capture, you may owe more. Filing the final return is how the true figure gets settled; the NTA warns that missing the deadline can bring additional tax and delinquency charges.
Two different clocks. Income tax (national) is on this year's income and is what the final return above settles. Resident tax (jūminzei, local) is charged on last year's income and on Jan-1 residency, so it usually still follows you after you leave and may need its own arrangement — often the same tax agent, or a lump-sum deduction from final pay. Handle both, not just one. Full resident-tax explainer →
| Your situation | Best move |
|---|---|
| Simple case, likely a small balance, you have time before your flight | Option A — file the quasi-final return & pay before departure |
| You may be owed a refund, or your numbers aren't final yet | Option B — appoint a tax agent so they can file Feb 16–Mar 15 |
| Freelance / multiple income sources / property or investment income | Option B + a licensed zeirishi — get the return right, not rushed |
| You also have unpaid resident tax that will outlast you | Arrange a nōzei kanrinin or lump-sum deduction for that too |
| You've already left without doing either | Contact the jurisdictional tax office / a tax professional ASAP — delay adds penalties |
Guidance, not a ruling on your case. Whether you must file, the exact forms, and deadlines depend on your residency status, income, and municipality — the NTA and a licensed tax accountant are the authorities for your situation.
• Ask your employer whether they'll do a year-end adjustment for your final pay or whether you must file yourself.
• Decide Option A vs B — and if B, submit the Notification of Tax Agent and confirm your agent before your departure date.
• Settle or arrange resident tax separately (city/ward office).
• Keep your gensen chōshū-hyō (withholding slip), My Number, and Japanese bank details so a refund can actually reach you.
Related reading: Japan's resident-tax timing trap → and, if you're heading home, the leaving-Japan pension refund →.
Mio