Missed the Kakutei Shinkoku Deadline? You Can Still File

Missed the deadline? File a late kakutei shinkoku with minimal penalties. Full e-Tax guide, deductions, and refund claims for foreigners.

If you're reading this after March 16, 2026—don't panic. You can still file. Japan allows late filing (期限後申告), and if you act quickly, the penalties are small or even zero. This guide covers exactly what to do now, plus the full e-Tax walkthrough for anyone filing their 2025 (Reiwa 7) income for the first time.

This article covers the 2026 filing season for 2025 (Reiwa 7) income—that's income earned from January 1 to December 31, 2025.

Japan tax return deadline 2026 (income tax): The Kakutei Shinkoku filing window for Reiwa 7 (2025) income is February 16 to March 16, 2026. (March 15, 2026 is a Sunday, so the deadline shifts to Monday, March 16.)

Missed the deadline? How to file a late Kakutei Shinkoku (期限後申告)

If you didn't file by March 16, 2026, you need to file a late return (期限後申告 / kigen-go shinkoku). The NTA says: even if you forgot to file, submit your return as soon as you realize.

How to file late (it's the same process)

You use the exact same e-Tax system or paper process described in this guide. The NTA's Tax Return Preparation Corner (確定申告書等作成コーナー) stays open year-round—it doesn't shut down after March 16. Create your return, submit via e-Tax or mail it to your tax office, and pay the tax on the same day you submit.

Late filing penalties: what you actually owe

There are two possible extra charges when you file late:

1. Late filing surcharge (無申告加算税 / mushinkoku kasanzei)

This is a one-time penalty on top of your tax. The rate depends on when you file and who finds out first:

You file voluntarily before the NTA contacts you: 5% of the tax you owe.
You file after the NTA sends a pre-investigation notice (but before actual investigation): 10% on the first JPY 500,000, 15% on JPY 500,001–3,000,000, and 25% above JPY 3,000,000.
You file after a tax investigation: 15% on the first JPY 500,000, 20% on JPY 500,001–3,000,000, and 30% above JPY 3,000,000.

2. Delinquency tax (延滞税 / entaizei)

This is interest on unpaid tax, calculated daily from the day after the original deadline until you pay. For 2025 (Reiwa 7) income, the rates are:

First 2 months after the deadline: 2.8% per year (January 1 – December 31, 2026)
After 2 months: 9.1% per year (January 1 – December 31, 2026)

These rates are set annually.

Zero-penalty exception: If you meet all of the following conditions, the late filing surcharge is waived entirely: (1) you file voluntarily within 1 month of the deadline, (2) you pay the full tax amount by the original deadline, and (3) you haven't been penalized for late filing in the past 5 years.

What about refund-only filers?

If you're filing only to get a refund (for example, you overpaid through withholding), there is no penalty for filing late. The NTA allows refund claims up to 5 years from January 1 of the year following the tax year. You have until the end of 2030 for 2025 income.

Bottom line: If you owe tax and missed the deadline, file as soon as possible—every day of delay adds to the interest. If you're getting a refund, there's no rush, but why leave your money with the government?

Before you start: tax year, residency, and key Japanese terms

Before you touch e-Tax, get the basics right: the tax year, your resident status, and a few key Japanese terms you'll see in the filing screens.

Tax year and the 2026 filing period

Japan's income tax year is always January 1 to December 31. For this season, you are filing your income earned in 2025 (Reiwa 7).

The National Tax Agency (NTA) announces the filing period each year. For Reiwa 7 (2025) income, the period is February 16, 2026 (Mon) to March 16, 2026 (Mon).

Resident status (why foreigners should care)

Your tax obligations depend heavily on whether Japan considers you a resident or non-resident for tax purposes.

The NTA explains that you are a non-resident unless you have a domicile in Japan or have had a residence continuously for one year or more. Non-residents are generally taxed only on Japan-source (domestic source) income.

Many expats also hear the term non-permanent resident (NPR). A common working definition used in professional summaries is: a foreign national who has stayed in Japan for an aggregate of 5 years or less within the past 10 years. This can affect how some foreign-source income is taxed.

Important: The NPR rules can get technical (especially when overseas income and remittances are involved). Use this guide to file confidently, but confirm your status if you have overseas investments, overseas payroll, or complex cross-border situations.

Minimum Japanese you need (quick glossary)

The return-prep screens are mostly in Japanese, so recognizing key labels saves time. (Even the NTA notes that the online "filing assistance/return preparation" instructions are only in Japanese.)

確定申告 (kakutei shinkoku): final tax return
確定申告書等作成コーナー: Tax Return Preparation Corner (the main online tool)
e-Tax (イータックス): electronic filing/submission system
マイナンバーカード: My Number Card
マイナポータル連携: MyNaPortal linkage (auto-import documents/data)
源泉徴収票 (gensen choushuu-hyou): withholding slip from your employer
控除 (koujo): deduction
還付 (kanpu): refund
納付 (noufu): payment
期限後申告 (kigen-go shinkoku): late filing (after the deadline)
無申告加算税 (mushinkoku kasanzei): late filing surcharge
延滞税 (entaizei): delinquency tax / late payment interest

Do you need to file? Common cases for foreign residents

Start here. Most "I'm not sure" situations become obvious when you separate (1) salary income and year-end adjustment from (2) side income and (3) freelance/business income.

Decision path (beginner-friendly)

Are you an employee with one employer in Japan?
- Usually NO: most wage earners don't need to file because income tax is settled through year-end adjustment (nenmatsu chosei).
- But YES if you fall into one of the "must file" cases below.
Do you have side income or "other income"? (freelance work, overseas income, selling online, crypto gains, rental income, etc.)
- Often YES if your total income excluding employment and retirement income is over JPY 200,000.
Are you mainly freelancing / self-employed in Japan?
- Almost always YES (you're responsible for calculating and paying your own income tax, and filing is how you do it).
Are you leaving Japan (or already left) and still need to settle taxes?
- Yes, plan ahead: you may need a tax agent in Japan or you may need to file/pay before departure (quasi-final return).

Employees: the most common "must file" triggers

If you're a salary worker, these are the big triggers the NTA lists for when wage earners must file a final return:

Your employment income exceeds JPY 20,000,000.
You have other income over JPY 200,000 (excluding employment and retirement income).
You had two or more employers, and the non-primary salary + other income exceeds JPY 200,000.

If you're not sure what counts as "other income," treat it as a flag to double-check (or ask the NTA consultation center or a tax professional).

Even if you don't have to file, you might want to (refund filing)

You can file a return just to claim a refund (for example, if too much was withheld). The NTA explains you can request a refund up to five years from January 1 of the following year.

This is especially common for foreigners who left a job mid-year and didn't get a year-end adjustment, or people claiming deductions like medical expenses or donations.

How to file: e-Tax online (smartphone/PC)

In 2026, the easiest path for most foreigners is: use the NTA's online preparation tool, submit via e-Tax, and (if possible) use MyNaPortal linkage so your documents auto-fill. This process works the same whether you're filing on time or late.

Step 0: Choose your login/submission method (My Number card vs ID/password)

There are two major ways individuals submit via e-Tax:

My Number Card method (マイナンバーカード方式): the standard approach for most people, and required for smooth MyNaPortal linkage.
ID/Password method (ID・パスワード方式): a simplified method for people who already completed the in-person setup.

2026 update that matters: the e-Tax helpdesk states that the NTA stopped issuing new ID/password credentials from October 1, 2025. If you don't already have them, you generally can't start with the ID/password method now—plan to use a My Number Card.

The e-Tax site also explains the ID/password method is a temporary measure and is limited to filing from the Tax Return Preparation Corner.

Step 1: Prepare what you'll need (foreigner checklist)

Gather these before you start. If you can't read Japanese well, this is where asking your employer/insurer for the exact document name helps.

My Number Card (physical card) and your PINs (if using the My Number Card method)
Employer documents: 源泉徴収票 (withholding slip) for 2025, and any additional statements your company provides
Deduction certificates (common examples):
- Life insurance / earthquake insurance premium deduction certificates (from your insurer)
- National pension/social insurance proof (from the issuer)
- Furusato Nozei donation certificates/receipts (from municipalities or platforms)
- Medical expense totals (or medical expense notification info)
Bank account details for refunds (account name in katakana is often requested)
If you freelanced: your income records and expense records for 2025 (receipts, invoices, summaries)

Step 2: Go to the official filing tool

Use the NTA's Tax Return Preparation Corner (確定申告書等作成コーナー) and follow the guided questions to generate the correct forms:

You can either submit electronically (e-Tax) or print and mail, and the NTA describes this workflow on its refund-filing guidance.

Step 3: Smartphone flow (what to expect)

If you want to file on a phone, the e-Tax helpdesk points to the smartphone manual and shows that the flow differs based on (a) tax type, (b) submission method, and (c) whether you use MyNaPortal linkage.

Open the Tax Return Preparation Corner and tap 作成開始 (Start creating).
Select the tax year (for this season: Reiwa 7 / 2025 income).
Choose submission: e-Tax.
Choose method:
- マイナンバーカード方式 (My Number Card method), or
- ID・パスワード方式 (only if you already have it)
If prompted, choose whether to use マイナポータル連携 (MyNaPortal linkage) to import documents automatically.
Enter income, then deductions, then confirm your refund/payment amount, then submit.
After submission, save your receipt/confirmation (受信通知) and any PDFs you download.

Step 4: Make MyNaPortal do the work (auto-import documents)

MyNaPortal linkage can reduce the amount of manual Japanese data entry by importing eligible certificates and filling them into the correct deduction fields.

The NTA lists examples of what can be auto-imported into the income tax return, including:

Medical expense notification information (医療費通知情報)
Furusato Nozei / donation certificates (寄附金受領証明書・寄附金控除に関する証明書)
Insurance premium deduction certificates (such as life insurance and earthquake insurance)
Withholding slip data (源泉徴収票情報) when available

Check the NTA's MyNaPortal linkage page for the latest list of eligible "deduction certificates, etc." and any timing/coverage notes (some items become available after certain dates).

Step 5: If you get stuck (official help)

If you need official guidance, the NTA provides a national consultation route.

National Tax Consultation Dial (Japan): 0570-00-5901
Follow the voice guidance (for individual Kakutei Shinkoku questions, select the option for personal filing inquiries as instructed)
Typical hours: 9:00–17:00 on weekdays (closed weekends/holidays and year-end/New Year period)

If you can't call that number (for example, some IP phones starting with "050"), the NTA explains you can call your local tax office's main number and follow the guidance to connect.

Deductions, refunds, and after you submit

This is where many foreigners either (a) get money back or (b) accidentally miss money they're entitled to. Below are the most common deductions and what to do after e-Tax submission—including leaving Japan.

Medical expense deduction (医療費控除): the key numbers

If you paid medical costs for yourself or family members you support, you may be able to claim the medical expense deduction.

The NTA states the deduction is calculated roughly as: (medical expenses paid − reimbursements) − JPY 100,000 (or 5% of total income if total income is under JPY 2,000,000), with a maximum deduction of JPY 2,000,000.

Paperwork rule: you generally need to attach a medical expense statement (医療費控除の明細書). Receipts typically don't need to be attached, but the NTA explains you must generally keep them for 5 years in case the tax office requests them.

Self-medication tax system (セルフメディケーション税制): an alternative

If you don't qualify for (or don't benefit from) the regular medical expense deduction, there's an alternative system for eligible OTC purchases.

The NTA explains this system is mutually exclusive with the regular medical expense deduction, and applies when eligible purchases exceed JPY 12,000, capped at JPY 88,000. It's available for purchases during the period January 1, 2017 to December 31, 2026.

Furusato Nozei (ふるさと納税): donation deduction + One-Stop warning

Furusato Nozei donations are deductible for income tax and residence tax for the portion exceeding JPY 2,000.

Very common foreigner mistake: if you used the One-Stop Special system (ワンストップ特例) but you end up filing Kakutei Shinkoku anyway (for example, because of medical expenses or side income), the NTA says the One-Stop application becomes invalid. You must include those donations in your return and calculate the deduction properly.

Life insurance premium deduction (生命保険料控除): what to ask your insurer for

If you paid life insurance/medical care insurance/personal pension insurance premiums, ask your insurer for the insurance premium deduction certificate (生命保険料控除証明書). The Tax Return Preparation Corner can calculate the deduction based on what you enter/import.

The NTA's guidance shows the deduction is calculated by category (new/old contracts and insurance types) and the total life insurance premium deduction is capped (commonly shown as a maximum of JPY 120,000 in the preparation guidance).

Dependent deduction for overseas family (国外居住親族の扶養控除): sending money home

If you send money to family members in your home country, you may be able to claim a dependent deduction (扶養控除) for them—potentially saving you JPY 380,000 to 630,000 in taxable income per dependent (income tax), plus a separate resident tax deduction.

Who qualifies? Your overseas family member must:

Be a relative within the 6th degree of kinship (parents, siblings, grandparents, aunts/uncles, etc.)
Have annual income of JPY 580,000 or less (updated from JPY 480,000 for Reiwa 7 income onwards)
Be financially supported by you

Important 2023 rule change (still applies): Since 2023 (Reiwa 5), dependents aged 30 to 69 living overseas face stricter rules. They can only qualify if they meet one of three conditions:

Studying abroad (left Japan to study overseas)
Have a disability
Received JPY 380,000 or more from you during the year for living or education expenses

For most foreign workers sending money to parents or siblings back home, condition 3 is the key path. If your family member is aged 30–69, you need to prove you sent at least JPY 380,000 during the year.

Dependents under 30 or 70 and older are not subject to these extra conditions.

Required documents (2 categories):

親族関係書類 (Shinzoku-kankei shorui) — Documents proving the family relationship: birth certificates, family registers, or government-issued documents from your home country (with Japanese translation)
送金関係書類 (Soukin-kankei shorui) — Remittance receipts from your bank or transfer service proving you sent money to that specific person. Keep all transfer receipts from the year. (If you sent 3 or more times, you may submit a summary list plus the first and last receipts.)

Practical tip: Use a bank transfer or remittance service that clearly shows the sender name, recipient name, amount, and date on receipts. Cash-in-hand or informal transfers are very difficult to prove to the tax office.

2026 "Reiwa 7 income" update to know: basic deduction changes

If you're filing 2025 (Reiwa 7) income in 2026, note that the NTA's basic deduction (基礎控除) table shows revised deduction amounts by income band for Reiwa 7 and later years, including a higher basic deduction for lower income bands (for example, an income band with a 95万円 basic deduction).

The same NTA page also notes that for non-residents, the basic deduction maximum is 58万円.

Refunds: when you get paid and how far back you can claim

If your withholding was too high (or you're claiming deductions/credits), you may get a refund after you submit. Refunds are usually sent to the bank account you register in your return.

Even if you weren't legally required to file, the NTA explains you can file a return for refund and you can submit a request for refund up to 5 years from January 1 of the following year.

After you submit: what to keep, what to fix, and what if you're leaving Japan

Keep your records: for some deductions (like medical expenses), you may need to retain documents for years. Don't throw away receipts or certificates until you're sure you've met the retention period.

If you made a mistake: don't panic. Japan has procedures to correct filings, but what you should do depends on whether you underpaid or overpaid.

If you will leave Japan: the NTA explains that if you leave Japan and lose tax residency but still need to handle return/payment procedures, you generally need to appoint a tax agent in Japan and submit the required notification. If you leave without doing that, you generally must file a quasi-final return and pay tax before departure.

Common "foreigner situations" (quick notes)

Short assignment / non-resident: The NTA defines non-resident status (no domicile and not continuously resident for 1 year or more) and explains non-residents are taxed on domestic source income.
Paid from overseas while working in Japan: The NTA gives an example where a foreign employee classified as a non-resident works in Japan but is paid from the home country without Japanese withholding; in that situation, a quasi-final return and payment before leaving Japan may be required.
Non-permanent resident (NPR) awareness: Japan has a special NPR framework for some foreign residents; professional summaries commonly use the "5 years or less in the past 10 years" rule of thumb, but your exact tax treatment can vary based on income type and how funds move.

Quick FAQ (foreigners filing in 2026)

Q: I only have one job in Japan. Do I need to file?
A: Usually no—most wage earners are covered by year-end adjustment. But you must file if you meet the NTA conditions (for example, high salary or other income over JPY 200,000).

Q: Can I file Kakutei Shinkoku with only a smartphone?
A: Yes. The e-Tax helpdesk provides smartphone flows and manuals; the steps differ depending on whether you use MyNaPortal linkage and your submission method.

Q: Can I still start using the ID/Password method in 2026?
A: If you don't already have it, likely not—the NTA stopped new issuance from October 1, 2025.

Q: I did Furusato Nozei with One-Stop—what if I file anyway?
A: One-Stop becomes invalid if you file Kakutei Shinkoku, so include the donations in your return.

Q: I send money to my family overseas. Can I get a tax deduction?
A: Yes—if your family member qualifies as a dependent (low income, supported by you). You'll need proof of relationship and remittance receipts. Note: since 2023, dependents aged 30–69 must meet extra conditions (e.g., you sent them at least JPY 380,000 during the year).

Q: I'm leaving Japan soon—what's the #1 thing to remember?
A: Decide whether to appoint a tax agent in Japan; if you leave without doing so and you still must file, you may need a quasi-final return and payment before departure.

Q: I missed the March 16 deadline. Am I in trouble?
A: Not if you act quickly. File as soon as possible using e-Tax or at your tax office. If you file voluntarily within 1 month and pay in full, the surcharge can be waived entirely. Even outside that window, self-reporting before the NTA contacts you keeps the penalty at just 5%.

Q: I'm only filing to get a refund. Is there a penalty for being late?
A: No. Refund-only filers face no late filing penalty. You can claim your refund for up to 5 years.

Practical tip: If you're missing a key document, ask for it using the Japanese name (for example, 源泉徴収票 for your withholding slip, 生命保険料控除証明書 for life insurance, and 寄附金受領証明書 for Furusato Nozei).

If you're filing via e-Tax, these LO-PAL guides can help with common setup and paperwork issues foreigners run into:

Need More Help? Ask on LO-PAL

If you want to know more about this topic or need specific local information (for example, what to bring to your local tax office, how to request documents from your employer, or how to read a deduction certificate), ask a local Japanese person on LO-PAL.

On LO-PAL, you can post a question or request a task, and local Japanese helpers in your area can respond. We support multiple languages (English, Chinese, Vietnamese, Portuguese, Korean, Nepali, Tagalog, Indonesian, and Spanish), so you can get practical help even if your Japanese is still beginner level.