Japanese Tax Return (Kakutei Shinkoku): Who Files and How to Do It

What kakutei shinkoku is

Kakutei means fixed or final, and shinkoku means declaration. In the return you declare your income for the previous calendar year, subtract deductions, calculate the income tax, and compare it with the tax already withheld. If you paid too much you get a refund (kanpu); if you paid too little you pay the difference.

The return also feeds into your resident tax. The tax office passes the information to your city, so you do not file a separate resident tax return when you file kakutei shinkoku.

Four words on every form

Your employer gives you the gensen chōshūhyō by the end of January, or when you leave the company. If you lost it, ask HR to reissue it: gensen chōshūhyō o saihakkō shite itadakemasu ka.

Who must file and who files by choice

The exact rules and amounts are set in the tax law and change from time to time, so treat these as the common cases and check the National Tax Agency's page for your year.

Refund-only returns, kanpu shinkoku, are not limited to the February to March season: you can file them from January, and for several past years. Returns that show tax to pay must be filed in the season.

The season and the documents

• January: employers hand out withholding slips; insurance companies and pension offices send deduction certificates.
• From January: refund returns can be filed.
• Mid-February to mid-March: the main filing period. Tax due is paid by the mid-March deadline, unless you set up automatic debit (furikae nōzei), which takes it later.
• Gather your My Number card or notice and photo ID, withholding slips, deduction certificates (控除証明書), receipts or the medical expense statement (医療費控除の明細書), and your bank details for a refund.
• Spring: refunds arrive in your bank account, often within weeks for online returns.

Deduction certificates come from different places. Life and earthquake insurance companies send theirs in autumn; if you paid national pension premiums yourself, the Japan Pension Service sends a certificate too, and national health insurance premiums you paid can be deducted using your payment records. Medical receipts are not submitted any more: you list them on the statement and keep them at home for several years.

e-Tax, the online form or the tax office

All three routes start from the same place: the National Tax Agency's online tax return creation page, kakutei shinkokusho tō sakusei kōnā. It asks questions, does the arithmetic and produces the forms.

If you file for a business, ask about the blue return, aoiro shinkoku (青色申告), which gives extra deductions but must be applied for in advance and needs proper bookkeeping. If you leave Japan with tax matters open, appoint a tax agent before you go.

At the consultation venue

Consultation venues are crowded in early March. Go early in the season, bring every document in one folder, and know what you want before you reach the desk. Staff speak Japanese, sometimes with simple English; short, clear sentences work best.

Before you leave, make sure you have a copy of the return, the hikae. You may need it later to prove your income, for example when renewing a visa, applying for a loan or enrolling a child in daycare.

Mistakes that delay a refund

• Waiting until the last week, when venues have long queues and some stop handing out tickets early in the day.
• Forgetting the withholding slip from a job you left in spring.
• Filing a return after using the furusato one-stop exception without listing the donations.
• Entering a bank account under a different name; refunds go only to the taxpayer's account.
• Forgetting that a mistaken return can be corrected: ask the tax office about filing an amended return rather than ignoring it.
• Not knowing the My Number card PIN. Several wrong attempts lock the card, and unlocking it means a trip to the city office.
• Claiming a family member abroad as a dependant without the documents the tax office requires, such as proof of relationship and of money sent.

After you file: refunds, payments and corrections

If your return shows a refund, it is paid into the account you entered, usually a few weeks after an online return and somewhat longer after a paper one. You can check progress through e-Tax, and the tax office sends a notice when the money is paid. If your return shows tax to pay, you can pay at a bank, at a konbini with a QR code printed from the online system, by card through the official payment site, or by automatic debit if you applied for it in advance.

Mistakes happen. If you find that you claimed too little, for example you forgot a receipt, you can ask for a correction, kōsei no seikyū. If you claimed too much, file an amended return, shūsei shinkoku, before the tax office contacts you. Both are routine, and the tax office telephone consultation centre can tell you which applies. Keep a copy of your return and the documents for several years.

Read the form before you file

The online form asks dozens of yes-or-no questions in Japanese. Copy any question you cannot follow into Mocchi and ask for a plain explanation; for a full sentence, /explain breaks down each word and the grammar. Mocchi remembers the tax words you have already met, so the second year's return is far easier than the first.

If you plan to go to a consultation venue, rehearse the conversation first: ask Hana-sensei in AI Sensei to play the staff member at the desk and practise explaining your income and the deduction you want.