If you make a profit on crypto assets (cryptocurrency) on an overseas exchange (MEXC, BingX, etc.), you file it as miscellaneous income, the same as with a domestic exchange. But because there is no 'annual transaction report' like a domestic exchange provides, you have to gather your transaction history, convert it to yen and calculate your gain or loss yourself. Put this off, and you may end up going back through a full year of trades in February or March of the following year, forced into the unfavourable calculation of treating 5% of the sale price as the acquisition cost because you no longer know the real figure.
Based on the National Tax Agency's 'Tax Treatment of Crypto Assets, etc.: FAQ' (last revised December 2025 (Reiwa 7)) and its procedural guidance, this article sets out how to file your tax return in four steps: (1) preparing your transaction history and converting it to yen, (2) gain/loss calculation using the total-average and moving-average methods and the NTA's calculation sheet, (3) filing via the tax return preparation corner, and (4) how to pay. It is based on the law and procedures as they stood on 22 September 2026.
Overseas exchange crypto profit also requires a tax return (miscellaneous income, aggregate taxation)
Residents of Japan owe income tax on their worldwide income, regardless of where it arose. Profit from crypto-asset transactions is classified in principle as miscellaneous income (other miscellaneous income), and is filed under aggregate taxation together with salary and other income (NTA FAQ 2-2). Profit from overseas exchanges is classified and calculated the same way. The main conditions requiring a tax return are as follows.
| Situation | Condition that requires a return | Note |
|---|---|---|
| Salaried employee (one employer, year-end adjustment done) | Total of income other than salary and retirement income (including crypto profit) exceeds ¥200,000 for the year | Resident tax must still be declared even at ¥200,000 or under |
| Salary income above ¥20,000,000 | Must file a return regardless of amount | The ¥200,000 rule does not apply |
| Not a salaried employee (sole proprietor, full-time trader, etc.) | Total income exceeds the total of income deductions such as the basic deduction | The ¥200,000 rule is written for salaried employees |
| A year with only losses | No obligation to file an income tax return (filing is still allowed) | Keep your transaction history and calculation records |
※ The '¥200,000' threshold is judged on 'profit (income)' after deducting necessary expenses such as the cost of disposal and fees — not on the sale amount.
The filing period runs from 16 February to 15 March of the following year (if 15 March falls on a weekend or public holiday, the next business day). If you file an income tax return, the content is shared with your municipality for resident tax, so no separate resident-tax filing is needed.
Step 1: Download your transaction history and convert it to yen
Domestic crypto-asset exchange service providers, at the National Tax Agency's request, issue an 'annual transaction report' listing the year's purchase quantity, purchase amount, sale quantity and sale amount, but overseas exchanges have no equivalent system. NTA FAQ 2-7 advises confirming the acquisition cost and sale price for transactions through an overseas crypto-asset exchange service provider using the following methods.
- Check the amount from the withdrawal from your bank account when you bought crypto assets, and the deposit into it when you sold them
- Use the exchange's transaction history together with the trading rates published by the crypto-asset exchange service provider to confirm the acquisition cost and sale price
- If the correct amount becomes clear after filing, correct it through an amended return or a request for reassessment
- 01Download each exchange's transaction history (spot, futures, deposits/withdrawals, fees, airdrops received, etc.) year by year
Many exchanges limit how far back or how long history can be retrieved, so get it at least once within the year
- 02Convert transactions denominated in foreign currency or another crypto asset, such as USDT, into yen at the exchange rate on the date of the transaction
Record the source of the rate you used (e.g., the exchange's published rate)
- 03Crypto assets sent from a domestic exchange to an overseas exchange carry over the acquisition cost from when they were bought domestically
The transfer itself is not a disposal
- 04Include crypto-to-crypto exchanges (such as BTC→USDT) and payments made with crypto assets in your list as disposals too (FAQ 1-2, 1-3)
Include crypto-to-crypto exchanges (such as BTC→USDT) and payments made with crypto assets in your list as disposals too (FAQ 1-2, 1-3)
If you have not kept transaction records and cannot confirm the acquisition cost, you are allowed to treat the acquisition cost as an amount equivalent to 5% of the sale price (FAQ 2-7). For example, if the acquisition cost of crypto assets sold for ¥5,000,000 is unknown, it is deemed to be ¥250,000, and ¥4,750,000 is calculated as income. If your actual acquisition cost was higher than this, failing to keep records results in a larger calculated income.
Step 2: Gain/loss calculation (total-average and moving-average methods) and the NTA's 'crypto-asset calculation sheet'
If you bought and sold the same type of crypto asset multiple times in a year, you calculate the cost of disposal for the year for each type of crypto asset, rather than income for each individual sale. The cost of disposal is calculated as '(1) the valuation of crypto assets held at the start of the year' + '(2) the total acquisition cost of crypto assets acquired that year' − '(3) the valuation of crypto assets held at the end of the year', where (3) is calculated using either the total-average method or the moving-average method (FAQ 2-4).
| Item | Total-average method | Moving-average method |
|---|---|---|
| How the unit price is calculated | The year's total purchase amount ÷ total purchase quantity (including the balance at the start of the year) becomes the average unit price for the year | Each time you buy, the previous balance and the new purchase are combined to update the average unit price |
| Cost of disposal in the worked example (5 BTC sold, sale proceeds ¥5,295,000) | ¥3,106,000 | ¥3,080,200 |
| Income in the worked example | ¥2,189,000 | ¥2,214,800 |
| Calculation effort | Can be calculated all at once at year-end | The unit price must be tracked for every transaction |
| Application | The total-average method applies (the statutory valuation method) if no notification is filed | Can be chosen if a notification form is submitted |
※ The worked example covers a case with four purchases and two sales between 1 March and 30 November (FAQ 2-4). Even for the same trades, that year's income differs depending on the valuation method.
The valuation method is chosen per type of crypto asset. Submit the 'Notification of the Valuation Method for Crypto Assets for Income Tax Purposes' to the director of the tax office for your place of tax payment by the filing deadline for the year you first acquired a crypto asset, or the year you first acquired a different type of crypto asset; if no notification is filed, the total-average method applies (NTA A1-20, FAQ 2-5). If you acquired the same type of crypto asset in an earlier year, you do not need to file again; to change methods, submit a 'Change Approval Application' by 15 March of that year and obtain approval (FAQ 2-6, A1-25). The notification form can be prepared and submitted using e-Tax software, or brought or sent in on paper.
The NTA's website publishes a 'crypto-asset calculation sheet' (Excel files for the total-average and moving-average methods): enter the year's purchase quantity, purchase amount, sale quantity, sale amount and the balance carried forward from the previous year, and it calculates your income (FAQ 2-8). The format assumes you enter figures straight from a domestic exchange's annual transaction report, but it works the same way for overseas exchange transactions if you enter the annual totals you converted to yen in Step 1. If you use many exchanges or trade many coins, you can also use a private gain/loss calculation tool that imports transaction history and calculates under both the moving-average and total-average methods, but keep the transaction history and rates behind the calculation yourself.
Income from crypto-asset margin trading (such as perpetual futures) is not eligible for the FX-style separate self-assessment taxation (the special taxation for miscellaneous income, etc. from futures transactions), and is filed under aggregate taxation (FAQ 2-12). It is combined as the same miscellaneous income as spot trading gains, and a futures loss can be offset against spot profit in the same year, but cannot be carried forward to the next year.
Step 3: Prepare and submit your return using the NTA's tax return preparation corner
Enter the income amount you calculated into your return using the NTA's tax return preparation corner. Salaried taxpayers enter the details from their withholding slip and then, in the 'miscellaneous income (other)' section, enter the crypto revenue amount (total disposal proceeds) and necessary expenses (cost of disposal, fees, etc.), with 'crypto assets' as the category and the exchange's name (kept in English for overseas exchanges) as the payer. The completed return can be sent via e-Tax using your My Number Card and a smartphone or an IC card reader, or printed and brought or mailed to the tax office.
- 01Open the tax return preparation corner and select 'income tax'
If using e-Tax with your My Number Card, prepare things such as linking Mynaportal beforehand
- 02Enter your salary income (withholding slip), and enter the crypto revenue amount, necessary expenses and income amount under miscellaneous income (other)
If you used multiple exchanges, enter the total for each type of crypto asset and keep the breakdown yourself
- 03Enter your income deductions (social insurance premiums, life insurance premiums, medical expense deduction, etc.) and check the tax amount
Enter your income deductions (social insurance premiums, life insurance premiums, medical expense deduction, etc.) and check the tax amount
- 04Submit via e-Tax, or print and submit in person
After submitting, save the receipt notification (e-Tax) or your copy
- 05In a year when a valuation-method notification is required (such as the year you first acquired crypto assets), submit it by the same deadline as your return, using e-Tax software or on paper
In a year when a valuation-method notification is required (such as the year you first acquired crypto assets), submit it by the same deadline as your return, using e-Tax software or on paper
The preparation corner's operation and the crypto-asset input fields are updated each year, so follow the on-screen guidance for the year you are filing. Keep the transaction history, yen-conversion calculations and expense receipts that support your return, together with your copy of the return, even after you submit it (retention periods differ depending on your income category and whether you keep books, so follow the guidance from your tax office).
Step 4: How to pay (the payment deadline is the same as the filing deadline)
You must pay the income tax you reported yourself by 15 March (the next business day if it falls on a weekend or public holiday), the same deadline as for filing. The tax office does not send a payment slip or notice even after you submit your return (NTA G-2), so you choose and arrange the payment method yourself.
| Method | Description | Note |
|---|---|---|
| Direct debit (furikae nozei) | Automatically debited from a bank account you registered beforehand, on a debit date set by the NTA | For income tax, the debit date falls after the filing deadline (announced each year by the NTA) |
| Direct payment (direct nofu) | Debited from a registered bank account via e-Tax | For those who filed via e-Tax |
| Internet banking, etc. | Pay from an internet banking account or an ATM | There are registration-based and input-based methods |
| Credit card payment | Pay via the 'National Tax Credit Card Payment Site' | The taxpayer bears the settlement fee |
| Smartphone app payment | Pay with a '○○ Pay' app via the 'National Tax Smartphone Payment Site' | Check the site for available apps and the amount limit |
| Convenience-store payment (QR code / barcode) | Pay at a convenience store using a QR code you generate at home, or a barcoded payment slip issued by the tax office | There is an amount limit |
| Counter payment | Pay at the counter of a financial institution or tax office | A payment slip is required |
※ If you miss the payment deadline, a late-payment tax is added for the period from the day after the statutory due date to the date of payment (NTA G-2).
For resident tax, your municipality calculates the tax amount based on your income tax return, and a notice arrives from June of the following fiscal year. Salaried employees can choose on the return whether it is deducted from their salary (special collection) or paid themselves (ordinary collection). If you do not want the resident tax on your crypto profit deducted from your salary, choose ordinary collection in the resident-tax section of the return.
Common mistakes when filing a tax return for overseas exchange crypto profit
- Excluding profit held in USDT from your return because you 'haven't converted it to yen yet': crypto-to-crypto exchanges are taxed at the time of the exchange (FAQ 1-3)
- Filing futures gains and losses under separate self-assessment taxation (FX treatment): crypto-asset margin trading is miscellaneous income under aggregate taxation (FAQ 2-12)
- Not including tokens received as a bonus or airdrop in your income: the market value at the time of receipt is income (FAQ 1-5, 1-7)
- Filing gains and losses separately by exchange: the rule is to combine and calculate them by type of crypto asset (FAQ 2-4)
- Setting the acquisition cost of crypto assets sent from a domestic exchange to ¥0: it carries over the acquisition cost from when it was bought domestically
- Assuming overseas exchange profit will not be noticed: CARF, which took effect in January 2026, provides a mechanism for information from exchanges to reach the NTA
Are overseas exchange crypto profits reported to Japan's tax office? CARF and audits in practice →
This article is a general summary of procedures based on National Tax Agency publications as of 22 September 2026, and is not individual tax advice. The calculation and filing method can differ depending on the details of your transactions and your income situation, so consult a tax accountant or your local tax office for specific decisions.
Frequently asked questions
Q. Do I need to file a tax return for profit made on overseas exchanges?
A. Yes. Residents of Japan owe tax on their worldwide income, and overseas exchange profit is also filed as miscellaneous income under aggregate taxation (NTA FAQ 2-2). Salaried employees need to file an income tax return if the total of income other than salary exceeds ¥200,000 for the year; resident tax must still be declared even at ¥200,000 or under.
Q. Overseas exchanges don't issue an annual transaction report — how do I calculate my gain/loss?
A. NTA FAQ 2-7 advises confirming the acquisition cost and sale price for transactions through an overseas exchange using your bank account's deposit/withdrawal records and the exchange's transaction history plus published rates. Download your transaction history, convert it to yen at the rate on the date of each transaction, and calculate the cost of disposal for each type of crypto asset using the total-average or moving-average method.
Q. Which should I use, the total-average method or the moving-average method?
A. If you file no notification, the total-average method (the statutory valuation method) applies. To use the moving-average method, submit the 'Notification of the Valuation Method for Crypto Assets for Income Tax Purposes' by the filing deadline for the year you first acquired a crypto asset (or first acquired a different type) (NTA A1-20, FAQ 2-5). To change methods, submit a change approval application by 15 March of that year and obtain approval.
Q. Can the NTA's 'crypto-asset calculation sheet' be used for overseas exchanges too?
A. Yes. Excel files for the total-average and moving-average methods are published on the NTA's website: enter the year's purchase quantity, purchase amount, sale quantity, sale amount and the balance carried forward from the previous year, and it calculates your income (FAQ 2-8). For overseas exchange transactions, enter the annual totals after converting them to yen.
Q. I didn't keep transaction records and don't know my acquisition cost. What happens?
A. You are allowed to treat the acquisition cost of the crypto assets sold as an amount equivalent to 5% of the sale price (FAQ 2-7). If you sold for ¥5,000,000, the acquisition cost is deemed to be ¥250,000, and ¥4,750,000 is calculated as income. If you can gather materials that show the actual acquisition cost (bank account withdrawal records, exchange history, etc.), calculate based on those instead.
Q. Are gains and losses from crypto futures trading taxed the same way as FX, under separate self-assessment taxation?
A. No. Crypto-asset margin trading is excluded from the separate self-assessment taxation under the Act on Special Measures Concerning Taxation, and is filed as miscellaneous income under aggregate taxation (FAQ 2-12). It is combined with spot trading gains, and a loss can be offset within the same year's miscellaneous income, but cannot be carried forward to the next year.
Q. By when, and how, do I pay income tax?
A. You pay by 15 March of the following year (the next business day if it falls on a weekend or public holiday) — the same as the filing deadline — using direct debit, direct payment, internet banking, a credit card, a smartphone app, a convenience store, or a tax office counter (NTA G-2). No payment slip is sent even after you submit your return, so you must arrange this yourself. Paying late incurs a late-payment tax.
Sources
- National Tax Agency (Japan) | Tax treatment of crypto assets, etc.: FAQ, last revised December 2025 (PDF, Japanese) →
- National Tax Agency (Japan) | Tax Answer No. 1900: Salaried employees who must file a return (current as of 1 April 2026) (Japanese) →
- National Tax Agency | A1-20 Notification of the valuation method for crypto assets (income tax; total-average method applies if no notification; Japanese) →
- National Tax Agency | A1-25 Application for approval to change the valuation method for crypto assets (Japanese) →
- National Tax Agency (Japan) | Tax treatment of crypto assets (Japanese) →
- National Tax Agency | Tax return preparation corner (Japanese) →
- National Tax Agency | G-2 How to pay national taxes (due dates, direct-debit dates, payment methods; Japanese) →
- National Tax Agency (Japan) | Tax Answer No. 2024: Filing after the deadline (penalty for failure to file, late-payment tax) (Japanese) →
- National Tax Agency (Japan) | Automatic exchange of information under the Crypto-Asset Reporting Framework (CARF) (Japanese) →
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