Annual Income Tax Declaration
/ What is this form?
Kakutei Shinkoku (確定申告) is Japan's annual individual income tax return process, administered by the National Tax Agency (NTA). The filing period runs from February 16 to March 15 each year (for the prior calendar year's income). Japan operates primarily on a pay-as-you-earn (PAYE) system called Gensen Chōshū (源泉徴収) — employers withhold income tax from salaries throughout the year and perform a year-end tax adjustment (年末調整, Nenmatsuchōsei) to reconcile withholding with actual tax liability. Most salaried employees therefore do not need to file a tax return.
However, self-employed workers, freelancers, those with rental or investment income, high earners (income above ¥20 million), and those who want to claim certain deductions (medical expenses, housing loan credit in the first year, large charitable donations) must or should file Kakutei Shinkoku. Foreign residents working in Japan who have income from their home country or foreign investments must also include this in their Japanese tax return.
Japan has invested significantly in its e-Tax system, which allows online filing with a My Number card. Physical submission at local tax offices is also accepted. The return uses Form A (simplified, for salary and pension income) or Form B (comprehensive, for all income types including business income).
/ Who needs this form?
/ What you need before you start
/ Step-by-step guide
/ Key fields explained
| Field | What to enter | Common mistake |
|---|---|---|
| 所得の種類 (Income Types) | Categorize income: Employment income (給与所得), Business income (事業所得), Real estate income (不動産所得), Capital gains (譲渡所得), Miscellaneous income (雑所得), etc. Each category has its own calculation rules. | Foreign residents categorizing foreign salary income as non-taxable — Japan taxes worldwide income for tax residents. Foreign salary must be reported. |
| 医療費控除 (Medical Expense Deduction) | Total qualifying medical expenses paid during the year. The deduction is: (Total medical expenses - insurance reimbursements) - ¥100,000 (or 5% of total income if lower). | Including over-the-counter vitamins, health foods, or cosmetic procedures — only medically necessary expenses are deductible. However, prescription medications and medically recommended supplements may qualify. |
| 源泉徴収額 (Withholding Tax Already Paid) | Total income tax withheld by employers as shown on your 源泉徴収票 (withholding slip). This is your prepaid tax credit against your total liability. | Forgetting to include withholding from side income (speaking fees, freelance payments) — any payment with withholding tax withheld generates a 源泉徴収票 that must be included. |
/ Common mistakes to avoid
/ Frequently asked questions
Usually not — employers handle year-end adjustment (年末調整) for most salaried employees. However, you must file if your annual salary exceeds ¥20 million, you have multiple employers, or you want to claim certain deductions (large medical expenses, first-year housing loan deduction).
Furusato Nōzei (hometown tax donations) allows you to donate to local governments and receive a tax deduction plus goods (typically food, crafts). Up to certain income-based limits, the donation reduces your local residence tax by the full donation amount minus ¥2,000. Over 10 million people participate annually.
Yes, if you had Japanese income in the year of departure. You file a 'departure return' (出国前確定申告) before leaving, or appoint a tax representative (納税管理人) to file on your behalf after departure.
Japan has tax treaties with over 80 countries. Treaties typically prevent double taxation on income — you can claim a foreign tax credit in Japan for taxes paid abroad. Consult a tax accountant (税理士) for country-specific treaty details.