Crypto users must complete and submit different tax forms based on the types of crypto activities they engaged in and the platforms they used:
formulaire 2042: the main tax return form to declare all income, mandatory for all taxpayers. It can be filed individually or jointly for married taxpayers.
formulaire 2086: attached to Form 2042, this form is used to declare capital
gains and income transactions, including any gains or losses.
formulaire 2042 C: for mining income or other income considered as BNC.
formulaire 3916-bis: to declare any cryptocurrency accounts opened outside France.
In this article we'll cover all the aspects of these forms and how you can easily compile them thanks to CryptoBooks.
ℹ️ The complete guide step by step is inside the tax return report
This guide provides an overview of the most important things to know about the fiscal forms. For a complete step-by-step guide, please download your precompiled tax return report.
Declaration deadline
The main deadline for submitting the French income tax return is usually in May or June, and it varies by department and filing method (online vs. paper).
Department | Tax Return Deadline |
Paper declaration | 20 May 2025 |
1 - 19 (and non-residents) | 22 May 2025 |
20 - 54 | 28 may 2025 |
55 - 974/976 | 5 June 2025 |
The CryptoBooks precompiled Report
The report you receive from CryptoBooks is designed to help you fill out your French tax return correctly, providing both pre-calculated figures and clear instructions on where to enter them in the official forms.
The report is divided into three main documents:
disposals declaration: a PDF containing all the data needed to declare each transaction that generated a capital gain or loss in Form 2086, plus your final result to be reported (if filing on paper) in Form 2042 C
income declaration: a summary of mining and other BNC (non-commercial) income, with the information required to complete Form 2042 C PRO
foreign crypto exchange declaration: a compilation of all available details for the non‑French exchanges you connected to CryptoBooks, to help you complete Form 3916‑3916bis
Each document of the CryptoBooks report includes a detailed guide on how to complete the corresponding part of your tax return. You’ll also find attached a complete list of your taxable transactions, which you can either submit with your tax declaration or keep for your records in case of a tax audit.
Capital gains and losses
If you realized gain or losses during the fiscal year you are required to fill out 2 different tax Forms: 2086 and 2042 C.
Form 2086
Whenever you sell, exchange, use, or give away your cryptocurrencies, you trigger a capital gain or loss that must be reported on Form 2086 even if the final result is a loss.
In Form 2086, you need to fill out a column for each disposal as follows.
Field Name | Field description |
Date de la cession | Date of the disposal |
Valeur globale du portefeuille au moment de la cession | Total value of your crypto portfolio just before the disposal |
Prix de cession | Gross proceeds from the disposal |
Frais de cession | Fees paid for the disposal |
Prix de cession net des frais | Proceeds net of fees |
Soulte reçue ou versée lors de la cession | Cash adjustments (usuallyempty) |
Prix de cession net des soultes | Proceeds net of any cash adjustment |
Prix de cession net des frais et soultes | Final net proceeds after fees and cash adjustments |
Prix total d’acquisition | Total acquisition price of your entire portfolio (excluding fees) |
Fractions de capital initial contenues dans le prix total d’acquisition | Part of the acquisition price already used in previous disposals |
Soultes reçues en cas d’échanges antérieurs à la cession | Cash adjustments at acquisition (often empty) |
Prix total d’acquisition net | Net acquisition price after subtracting prior fractions |
Plus-values ou moins-values | Gain or loss for the transaction |
⚠️ You can declare a maximum of 100 transactions
Form 2086 allows you to declare up to 100 transactions. If you made more than 100, French authorities informally suggest aggregating transactions that occurred on the same day.
🪄 CryptoBooks: all your 2086 figures, aggregated when needed
We provide all the data you need based on the number of transactions you must declare. Where necessary, it will already be aggregated to fit within the limits of Form 2086. In addition, we provide a CSV with all non-aggregated transactions.
Form 2042 C
Depending on your final capital gains result, you must complete different fields on Form 2042 C:
if you have an overall gain, enter the amount on line 3AN
if you have an overall loss, enter it on line 3BN.
Also remember that if you wish to opt for the progressive income tax rate, you must check box 3CN.
Crypto Income
Not all crypto earnings are capital gains. Some are treated as non-commercial, non-professional income (BNC).
According to the French laws mining rewards must be declared at their value at the time of receipt as BNC income in Form 2042 C PRO.
For other reward types (staking, earning, airdrops, farming), many accountants align them with mining (declare as BNC at receipt), but there is no official interpretation stated in the material provided.
To learn more about how to manage rewards other than mining, read this guide.
Form 2042 C PRO
To declare crypto income (BNC) in Form 2042 C PRO, first sum the value of your rewards at the time of receipt. Then fill out different fields based on the total value you realized during the fiscal year.
If the total BNC amount to declare (sum of the value at receipt of the income categories you selected) is less than or equal to €77.700,00 enter it in box 5KU.
If the total is greater than € 77.700,00 enter it in box 5JG.
Foreign exchange accounts
If you maintain an account on a crypto exchange located abroad, you must declare it using Form 3916–3916 bis as part of your annual tax return.
Form 3916–3916 bis
For each exchange you'll need to provide:
identité du titulaire: provide your personal information; if an advisor manages the account, provide their details instead
nature du compte: select “Compte d’actifs numériques”
numéro du compte: add the opening date and, if the account has been closed during the year, the closing date
désignation de l’organisme gestionnaire du compte: if the exchange is recognized in the system, enter its PSAN code. Otherwise, select “Autre organisme” and provide the exchange’s name, postal address, and official website domain
modalités de détention: if the account is personally owned by you, select “Titulaire en propre du compte d’actifs numériques à l’étranger”
usage du compte: indicate whether it is for personal, professional, or mixed use
Your CryptoBooks report lists the foreign exchanges connected to your profile and, when available, includes PSAN details (code, name, postal address, URL).