Filing a Japan tax return (kakuteishinkoku) can feel overwhelming when you’re navigating a foreign tax system in a second language. But here’s the good news: once you understand the process, it’s more manageable than it looks. This guide walks you through everything you need to know about kakuteishinkoku in 2026, whether you’re a freelancer, a company employee with side income, or someone who left a job mid-year.
Who Needs to File a Kakuteishinkoku in Japan?
Not every foreigner in Japan needs to file a tax return — but many do, and skipping it when you’re required to file can lead to penalties. You must file a kakuteishinkoku if you are self-employed, a freelancer, or run your own business in Japan. You also need to file if you earn more than ¥200,000 in income outside of your main salaried job in a calendar year.
Company employees typically have their taxes handled through nenmatsu chosei (year-end adjustment) by their employer. However, if you resigned from a job during the year and your employer did not complete a nenmatsu chosei, you’ll need to file yourself. The same applies if you have rental income, foreign income, or significant investment gains.
For example, if you work full-time at an English school in Osaka and also earn ¥300,000 teaching private lessons on weekends, that side income pushes you into kakuteishinkoku territory. Always err on the side of filing — you may even get a refund.
Key Deadlines and the Filing Period
The kakuteishinkoku filing period runs from February 16 to March 15 each year. In 2026, this means you are filing for income earned during the 2025 calendar year (January 1 to December 31, 2025). Missing the deadline can result in late-filing penalties and added interest charges, so mark your calendar early.
If you are expecting a tax refund, you can actually file as early as January 1 — you don’t have to wait until February 16. This is a smart move if you want your refund processed faster. Refunds are typically paid directly into your Japanese bank account within 3 to 5 weeks of filing.
Late filers should know that the tax office does not aggressively chase foreigners, but outstanding tax debt can create serious problems when renewing a visa or applying for permanent residency. Don’t let it slide.
How to Actually File: Your Three Options
You have three practical ways to submit your kakuteishinkoku in Japan. Each has different levels of effort and Japanese-language requirement.
Option 1: e-Tax (Online Filing)
e-Tax is the Japanese government’s online tax filing system and is increasingly foreigner-friendly. You’ll need a My Number Card and a compatible IC card reader, or you can use the smartphone app. Go to the National Tax Agency website (nta.go.jp) and use their guided form builder to create your return. It’s available in English up to a basic level, though some screens are still in Japanese.
Option 2: Visit Your Local Tax Office
Every city and ward has a zeimusho (tax office) that handles kakuteishinkoku in person. During filing season, many offices set up dedicated counters with staff to assist you. Bring all your documents and they will often walk you through the forms. This is the best option if your tax situation is simple and you feel more comfortable getting face-to-face help.
Option 3: Hire a Tax Accountant (Zeirishi)
If your finances are complex — multiple income sources, overseas assets, or business expenses — hiring a zeirishi (certified tax accountant) is worth the cost. Fees typically range from ¥20,000 to ¥80,000 depending on complexity. Several tax accountants in Tokyo and Osaka specialize in handling returns for foreigners and offer English consultations.
Documents You Need to Prepare
Getting your paperwork together ahead of time makes the filing process much smoother. Here’s what you’ll typically need:
– My Number (individual number) — your 12-digit identification number
– Withholding tax certificate (gensen choshuhyo) — issued by your employer in January
– Receipts for deductible expenses — medical costs, business expenses, donations
– Bank account details — for receiving your refund
– Residency certificate (juminhyo) — sometimes required for first-time filers
If you have income from overseas, you may also need records of foreign earnings and any taxes already paid abroad, as Japan has tax treaties with many countries that prevent double taxation.
FAQ
Do foreigners have to pay taxes in Japan?
Yes. If you are a resident of Japan — meaning you have lived here for more than one year — you are taxed on your worldwide income, not just income earned in Japan. Short-term residents (under one year) are only taxed on Japan-sourced income.
What happens if I don’t file and I should have?
The tax office can issue a tax assessment based on estimated income, which is often higher than your actual liability. You’ll also face a non-filing penalty of 15% to 20% of the unpaid tax amount, plus interest. Repeated non-filing can complicate visa renewals and permanent residency applications.
Can I file a kakuteishinkoku in English?
The official forms are in Japanese, but the NTA’s online tool (確定申告書等作成コーナー) has basic English guidance. Many foreigners use a bilingual tax accountant or rely on English-language guides and communities like this one to navigate the process step by step.
Conclusion
Filing your Japan tax return (kakuteishinkoku) doesn’t have to be a stressful experience. With the right documents, a clear understanding of the deadlines, and the right filing method for your situation, you can get it done efficiently — and possibly even receive money back. The February 16 to March 15 window goes faster than you think, so start gathering your documents now.
If you found this guide helpful, explore more of our Japan resident finance guides on j-nav.com for advice on everything from opening a bank account to understanding the Japanese pension system. When in doubt, don’t guess — file, and file on time.
