Cryptocurrency and French Tax: What UK Expats Need to Know (2026)

A plain-English guide to declaring cryptocurrency as a French tax resident. Covers when gains are taxable, the flat rate that applies, which forms to use, what DAC8 means for you this filing season, and the account declaration obligation most people miss entirely.

If you hold cryptocurrency and you live in France, you have tax obligations — and from 2026, the French tax authority can see your activity more clearly than ever before. The rule has always been that crypto gains are taxable in France when you sell into fiat currency.

What's changed this year is that EU exchanges are now automatically transmitting your transaction data to the Direction Générale des Finances Publiques (DGFiP) under a directive called DAC8. That data arrives before your return does.

This guide covers what you need to declare, when gains are actually taxable, which forms to use, what rate applies, and the separate account declaration that most people don't know exists.

For a broader overview of how investment income is treated in France, see our guide to PFU vs Progressive Tax: Which Is Better for Your Investment Income?

What DAC8 Actually Changes for You

DAC8 is the EU's eighth Directive on Administrative Cooperation. In practical terms it means that from 2026, crypto-asset service providers — exchanges, wallet providers, trading platforms — operating anywhere in the EU must collect and automatically report user data to the tax authority of the user's country of residence.

If you are a French tax resident, that means the DGFiP.

The reports include your identity, account balances, and transaction volumes. This is the first filing season in which this data flow is live and operational. It doesn't change what you owe — the rules on crypto taxation in France predate DAC8 by several years. What it changes is that the DGFiP is now cross-referencing your declaration against data they already hold before your return is processed.

One thing worth noting: DAC8 covers EU-based and EU-compliant exchanges. If you use platforms based outside the EU, the automatic reporting doesn't apply — but your obligation to declare still does. More on that in the accounts declaration section below.

When Is Crypto Actually Taxable in France?

This is where most people get confused, because the UK rules and the French rules work quite differently.

In France, the taxable event for cryptocurrency is when you convert crypto into fiat currency — euros, sterling, dollars. A straight sale from crypto to bank account triggers the gain calculation.

Crypto-to-crypto exchanges are not taxable in France at the point of the swap. If you exchange Bitcoin for Ethereum, no gain is crystallised at that moment. The gain is deferred until you eventually convert to fiat. You do, however, need to track your cost basis carefully — because the gain you eventually pay tax on depends on what you paid for the original asset.

Using crypto to pay for goods or services does count as a disposal and triggers a taxable gain if you've made a profit.

Staking rewards and airdrops are treated differently and don't fall neatly into the gain calculation framework — if you receive staking income, take specific advice on how to categorise it, as the treatment is not yet settled.

The crypto-to-crypto rule is one of the most misunderstood aspects of French crypto tax. Many UK expats assume the rules work the same as in the UK (where crypto-to-crypto is taxable). In France, you can swap freely between cryptocurrencies without triggering a gain. The clock only starts when you cash out.

What Rate Applies?

Crypto gains in France are subject to the flat tax (PFU — Prélèvement Forfaitaire Unique) at 30%. This breaks down as 12.8% income tax and 17.2% in social charges (CSG/CRDS). See the PFU flat tax and social charges rates on the Taxpert reference data page →

You cannot opt for the progressive income tax scale for crypto gains — unlike dividends and interest, where the progressive scale option exists. The 30% flat rate is the only route.

The €305 exemption threshold: If your total gross crypto-to-fiat sales across the entire tax year are €305 or less, you are exempt from declaring gains. But this threshold is easily misread. It applies to the total value of all disposals, not just your profit. Sell €350 worth of crypto and make a £10 profit — you're over the threshold and the gain is fully taxable. The cliff-edge nature of this threshold catches people out.

Crypto losses cannot be offset against other income or other asset types. If you made a loss on crypto and a gain on shares in the same year, you cannot net them off. And unlike share losses, crypto losses cannot be carried forward to future years. Each year's crypto position stands alone.

Which Forms Do You Need?

This is where crypto diverges from every other income type on the French return. It has its own dedicated workflow.

Step 1: Form 2086 — complete this first

Form 2086 is the dedicated digital assets calculation form. You must complete it before touching your main return. It requires a transaction-by-transaction breakdown — not a single net figure. Every disposal during the tax year needs to be worked through the form individually.

This applies even if your total sales are below the €305 threshold. The form is mandatory regardless of whether any tax ends up being due. If you had crypto activity and don't file Form 2086, that's a compliance gap — not a minor one.

The net gain or loss from Form 2086 then transfers to your main supplementary return.

Step 2: Form 2042 C — transfer the result

Once Form 2086 is complete, the net figure transfers to Form 2042 C:

• Net gain → Box 3AN
• Net loss → Box 3BN

One important rule on household totals: boxes 3AN and 3BN must represent the combined total for the entire tax household — all transactions by all members, across all exchanges. If you and your partner both hold crypto, both sets of transactions go into a single Form 2086 calculation, and the resulting net figure lands in a single 3AN or 3BN box.

Working through Form 2086 transaction by transaction — applying the correct exchange rate to each disposal, calculating cost basis, offsetting gains and losses across household members — is genuinely the most time-consuming part of a French crypto declaration. Taxpert's filing assistant handles the exchange rate conversion and calculation summary, giving you the figures you need to complete Form 2086 without starting from a blank spreadsheet.

The Account Declaration Most People Miss

Separate from the gains declaration, there is a mandatory annual obligation to declare the existence of any foreign digital asset accounts you hold.

This is done via Form 3916-bis — a specific variant of the foreign account declaration form used for digital asset accounts. It applies to any cryptocurrency exchange or wallet provider based outside France: Coinbase, Kraken, Binance, and similar platforms all count.

The declaration must be made every year the account exists — not just when you make a transaction, and not just when you have a gain. A dormant account still needs to be declared. A loss-making account still needs to be declared.

The penalties for failing to declare foreign accounts are significant — up to €750 per undeclared account per year, rising to €1,500 per account if the account is held in a non-cooperative jurisdiction. These fines apply even when no tax is owed on the income from those accounts.

For more on how social charges interact with your overall tax position, and how an S1 certificate can affect the social charges element, see the linked guides.

Common Mistakes

1. Not filing Form 2086 because no tax is due. Form 2086 is mandatory even if your total sales are below €305, and even if you made a loss. The form documents your position for the tax authority regardless of the financial outcome.

2. Assuming crypto-to-crypto swaps are taxable. They aren't, in France. You only crystallise a gain when converting to fiat. Many UK expats apply the UK rules by default — this leads to over-declaring and potentially over-paying.

3. Treating the €305 threshold as a profit threshold. It applies to the total value of disposals, not the net profit. €400 worth of sales — even at a loss — takes you above the threshold and makes the position declarable.

4. Forgetting Form 3916-bis. The gains declaration and the account existence declaration are two entirely separate obligations. Filing Form 2086 correctly does not satisfy the 3916-bis requirement. You need to do both.

5. Using only one exchange's records. DAC8 means the DGFiP will receive data from each EU-compliant exchange separately. If your household holds crypto across multiple platforms, the Form 2086 calculation must consolidate all of them. The tax authority will see each exchange's report individually — your return needs to match the sum.

6. Ignoring losses. Even if you've made a net loss this year, you still need to complete Form 2086 and file Form 3916-bis. The loss is recorded in Box 3BN on Form 2042 C — it doesn't reduce your tax bill, but it documents your position.

Frequently Asked Questions

I hold crypto but haven't sold anything this year. Do I still need to declare?

You don't need to file Form 2086 or declare a gain if you made no disposals (no crypto-to-fiat conversions, no purchases using crypto). However, if your exchange or wallet is based outside France, you still need to file Form 3916-bis to declare the existence of the account — even if it was dormant for the year.

My crypto exchange is based in the UK, not the EU. Does DAC8 still apply?

DAC8 directly applies to exchanges operating within the EU. UK-based exchanges are not automatically within scope, though many comply voluntarily or under equivalent frameworks. Regardless of whether your exchange reports under DAC8, your obligation to declare gains and to file Form 3916-bis for foreign accounts is unchanged. DAC8 affects what the DGFiP can see — it doesn't change what you owe.

I made a loss on crypto this year. Can I offset it against my share gains?

No. Crypto losses in France are ring-fenced. They cannot be offset against gains from other asset types (securities, property) and they cannot be carried forward to future years. The loss is recorded on Form 2086 and transferred to Box 3BN on Form 2042 C, but it produces no tax benefit.

Do I pay social charges on crypto gains?

Yes. The 30% flat rate includes 17.2% in social charges (CSG/CRDS). However, if you hold a valid S1 certificate and tick boxes 8SH/8SI on Form 2042 C, your social charges on crypto gains are reduced to the solidarity levy rather than the full 17.2% — the same treatment that applies to dividends, interest, and securities capital gains. S1 holders will therefore pay a lower effective rate than the standard 30%.

What exchange rate do I use to calculate crypto gains in France?

You must convert all amounts into euros using a recognised rate at the date of each transaction. You cannot use a single year-end rate or an approximate figure. For guidance on which exchange rate sources are acceptable for French tax purposes, see our exchange rate guide.

I've never declared my Coinbase account on Form 3916-bis. What should I do?

If you've been holding a foreign crypto exchange account without filing Form 3916-bis, you can make amended declarations for prior years via a déclaration rectificative. It's better to correct this proactively than to wait for the DGFiP to identify the gap — particularly now that DAC8 is transmitting exchange data directly to them. Speak to your local tax office or a tax adviser about the best approach for your specific situation.