Do Not Declare Your Cryptos: Complete Guide 2025

Investing in cryptocurrencies today attracts more than 10% of the French population, eager to benefit from the opportunities of an expanding market. However, the issue of declaring crypto-assets for tax purposes raises many challenges: obligations, penalties, legislative novelties, and effective strategies to stay compliant. This complete guide for 2025 details all the implications of not declaring, the risks involved, and essential practices to optimize and secure your cryptocurrency investment.

Introduction

Since the advent of Bitcoin, Ethereum, and altcoins, the cryptocurrency revolution has transformed the global financial sector. This ecosystem, based on decentralization and blockchain technology, attracts individual investors, businesses, and wealth managers. However, this innovation faces increasingly strict regulation and tax implications that it is imperative to master to avoid any disputes with the tax authorities.

The potential gains from cryptocurrencies are undeniable, but a lack of vigilance regarding taxation exposes holders to significant penalties. The objective of this article: to provide a clear, comprehensive, and up-to-date view of the French rules in 2025 concerning the declaration of crypto-assets, to help each investor act responsibly and wisely.

Regulatory Context

Taxation of cryptocurrencies in France began to take shape in 2019. Two main obligations apply to all individuals residing for tax purposes in France:

  • Declaration of accounts opened, held, used, or closed abroad: Any person using foreign platforms to buy, sell, or store cryptocurrencies must declare these accounts annually through Form 3916-bis.
  • Declaration of capital gains realized: Any operation involving the sale of cryptocurrencies against fiat money (euro, dollar...) or when purchasing goods/services must be declared through Form 2086. Crypto-to-crypto transactions (exchange of one crypto for another) are not taxable and do not need to be declared.

Failing to comply with these obligations exposes taxpayers to significant tax and criminal penalties. French cryptocurrency platforms registered with the AMF (Financial Markets Authority) are generally not subject to the obligation to declare foreign accounts, unlike most European or international platforms.

Note: legislation is constantly evolving. A project foresees integrating cryptoassets into the calculation of "unproductive wealth" starting in 2026 for fortunes exceeding 1.3 million euros. Tax surveillance will be strengthened starting in 2027 with the entry into force of the European DAC8 directive, requiring platforms to communicate customer data to the French tax authority.

Analysis

Risks of Not Declaring Your Cryptos

Ignoring the obligation to declare cryptocurrencies is never a viable strategy: the consequences are severe and intensify each year.

  • Tax sanctions:
    The failure to declare an overseas crypto account is subject to a fine of €750 per undeclared account, increased to €1,500 if the total value of the accounts exceeds €50,000. Unreported capital gains lead to tax adjustments, including payment of owed taxes, a penalty of 10% for non-declaration, and interest on late payments. In cases of fraudulent activity, the penalty can reach up to 80%.
  • Criminal sanctions:
    In cases of proven fraud (intentional concealment), criminal proceedings may be initiated: fines up to €500,000 and/or imprisonment.
  • Increased monitoring:
    Tax authorities in France and the EU are intensifying their surveillance of transactions. Foreign and French platforms will be required to transmit user data through DAC8 starting in 2027, making concealment virtually impossible.

Tax authorities easily identify movements of funds and the possession of digital assets through flow analysis and collaborations with exchange platforms. The risk of detection increases significantly with these regulatory changes.

Tax Obligations: What Must Be Declared

There is sometimes confusion about what is actually taxable or needs to be declared:

  • Account declaration:
    • All accounts opened, held, used, or closed on foreign platforms must be declared using Form 3916-bis.
    • Only French platforms registered with the AMF are exempt from this requirement. Non-custodial accounts (wallets where you hold the private key, such as Ledger) are not included.
  • Capital gains declaration:
    • Capital gains realized from selling cryptocurrencies against fiat currency (euro, dollar, etc.) or purchasing goods/services are taxable and reportable via Form 2086.
    • If the annual total of sales does not exceed €305, no tax is due.
    • Cryptocurrency-to-cryptocurrency exchanges (energy, tokens) or trades involving stablecoins are not taxable.
    • Capital losses cannot be deducted from gross income; they can only offset capital gains within the same year in cryptocurrencies.
  • Asset holding declaration:
    • The mere holding of cryptocurrency assets (without sale) is not required to be declared unless it involves an overseas account.
    • For taxpayers with more than €1.3 million in crypto wealth (starting in 2026, pending final approval), a special declaration of "unproductive wealth" will be required.

Capital Gains Taxation in 2025

The tax applied to capital gains on cryptocurrencies in France is now well established:

  • Annual capital gains up to €305 are exempt from tax.
  • Beyond that, taxation is done at the flat withholding rate of 30% (12.8% income tax + 17.2% social security contributions).
  • Since 2023, it is possible to opt for the progressive tax scale on income if this rate is more advantageous (box 3CN on the declaration).
  • Sales exclusively against fiat money or purchase of goods/services are taxable: exchange transactions between different cryptocurrencies are not.

It is important to distinguish the rules applicable to individual taxpayers and companies, the latter often being subject to specific regulations (accounting, VAT, BNC/BIC).

Fines incurred in case of non-declaration

Fines for undeclared cryptocurrency accounts or capital gains are severe and increase progressively:

  • A fixed fine of €750 per undeclared account, increased to €1,500 if the total value of the accounts reaches or exceeds €50,000.
  • Tax adjustment on undeclared capital gains, with an additional 10% penalty for failure to declare, up to 80% in case of established fraud.
  • Criminal proceedings: fines that can reach €500,000, and up to 5 years in prison in case of deliberate and organized concealment.

Fines are systematically applied as soon as an offense is detected; there is therefore no "tolerance" or low-level fines concerning cryptocurrencies.

Recent and upcoming legislative changes

  • 2026:
    Integration of crypto-assets into the future "unproductive wealth": any crypto asset portfolio exceeding €1.3 million will be subject to special declaration, with capital gains taxed at 30%. (Subject to legislative confirmation.)
  • 2027:
    Entry into force of the DAC8 directive: cryptocurrency platforms will be required to automatically transmit client data to the French tax authorities. Detection of undeclared accounts will become almost instantaneous.

These developments aim to strengthen transparency in the French market and combat tax fraud associated with cryptocurrencies.

Frequently Asked Questions and Points of Attention

  • Are stablecoins taxable? Conversions between cryptocurrencies and stablecoins are not considered taxable operations, except if the stablecoin is subsequently converted into euros or used to purchase a good/service.
  • Do I need to declare a Ledger wallet? Holding crypto in a physical key or a non-custodial wallet does not require declaration, unless it is linked to an account on a foreign custodial platform.
  • How can I optimize declarations and taxation? Keep all documentation up-to-date: platform statements, transaction histories, deposit/withdrawal justifications. Retain all elements necessary to reconstruct flows in case of audit.

Strategies for investing in compliance with tax legislation

Compliance with tax obligations allows for serene investment and optimization of performance:

  • Maintain complete transparency in the management of your accounts: retention of supporting documents, anticipation of legislative changes, use of automated tracking tools.
  • Use registered French platforms AMF, which guarantee legal security and simplified declaration procedures.
  • Regularly review regulatory changes: any modification can impact taxation, declarations, or the valuation of your assets.

Effective Management of Cryptographic Assets

The proactive management of your crypto-assets ensures their protection and facilitates their declaration:

  • Keep an accurate record of your transactions, noting the date, nature of the operation, amount, type of asset, and platform used. This traceability is essential for calculating your capital gains and justifying your declarations.
  • Verify annually the compliance of your accounts: ensure that all active or closed foreign accounts are declared, even those used only once during the year.
  • Anticipate tax audits: prepare all supporting documents to respond to any request from the administration.

Best Practices and Errors to Avoid

  • Never omit the declaration of a foreign account, even if it has a low balance.
  • Do not neglect indirect conversions: any sale against fiat currency or purchase of goods/services with crypto triggers a declaration and taxation obligation.
  • Avoid unregistered or poorly regulated platforms: the risk of control, fund blocking, or forced declaration is higher.
  • Monitor new developments: in 2026 and 2027, announced changes (idle wealth, DAC8) will impose new reflexes and constraints on all crypto-asset holders.

Tax Optimization for Crypto Investors

Reduce Taxation on Capital Gains

  • Compare the flat withholding tax (FWT) at 30% with the progressive income tax rate. A lower tax rate may allow you to opt for the progressive rate if it proves more advantageous.
  • Divide your sales to remain below the threshold of €305 in annual sales subject to tax, within reason (be mindful of abuse of rights).
  • Record carefully all transaction-related expenses: exchange commissions, bank fees, which can be deducted from the taxable amount.

Structure Your Portfolio in Light of New Rules

  • Anticipate the inclusion of crypto wealth in the wealth declaration starting in 2026 if your crypto capital exceeds €1.3 million.
  • Consult tax experts or specialized software to maximize the accuracy and security of your declarations.
  • Prepare now the documentation required by the DAC8 directive starting in 2027: statements, identities, transaction receipts.

Practical Questions and Points of Attention for 2025-2027

  • Review all open foreign accounts: ensure they are up to date in the declaration.
  • Maintain a comprehensive history of all your crypto-to-crypto exchanges to correctly calculate capital gains when sold for fiat currency.
  • Consider estate developments: any crypto capital over €1.3 million will require new reporting obligations starting in 2026.
  • Prepare for tax transparency: opacity has become impossible since the strengthening of controls and the upcoming implementation of DAC8.

Conclusion: act in compliance and protect your investments

Failing to declare cryptocurrencies in France exposes one to major tax risks, severe criminal penalties, and increased scrutiny by authorities. Legislation, controls, and European cooperation make hiding accounts and capital gains increasingly risky. Adhering to tax obligations and optimizing declarations are the only safe ways to invest calmly in crypto-assets.

It is essential to stay informed about regulatory changes and adopt proactive and transparent management of portfolios. Adopt the solutions and strategies proposed in this guide to protect your assets, avoid disputes, and fully benefit from the potential of cryptocurrencies within the framework of current legislation.