Over 90% of France’s Crypto Gains Go Undeclared

Blockchain analytics firm Chainalysis says that the amount of potentially taxable crypto activity in France for 2025 was about $9.4 billion. By contrast, tax filings for the 2024 income year show only 24,000 individuals reporting a combined €368 million ($427 million) in net gains.

Breakdown of the estimated activity

Chainalysis splits the $9.4 billion figure into three components:

• $5.2 billion in payments
• $2.5 billion in capital gains
• $1.7 billion in income from mining, staking and similar sources

Tax filings vs. blockchain data

For the 2024 tax year, French authorities recorded about 24,000 taxpayers declaring €368 million in net crypto gains. This is up from roughly 7,700 taxpayers and €150.8 million the previous year, but remains a small share of the activity seen on‑chain.

Regulatory context

The EU’s eighth Directive on Administrative Cooperation (DAC8) took effect on 1 January 2026. It obliges crypto service providers in member states to collect detailed user and transaction data and share it with national tax authorities. From 30 September 2027, these authorities will exchange records across borders, aligning crypto reporting with existing banking information‑exchange frameworks.

Challenges and enforcement

Chainalysis notes that its global estimate of potentially taxable on‑chain activity for 2025 exceeds $457 billion, with Europe accounting for $125.1 billion and the United States $112.6 billion. The firm warns that compliance gaps may be above 90 % in some jurisdictions, citing Sweden as a comparable case.

In France, the flat tax rate on crypto capital gains is 31.4 % with an annual exemption of €305, meaning most realized profits are technically reportable. Yet the disparity between on‑chain estimates and declared gains suggests a large compliance shortfall.

Broader implications

CARF, the OECD‑backed Crypto‑Asset Reporting Framework, captures only about 14 % of global taxable activity, leaving roughly 86 % outside its scope. Decentralized wallets, peer‑to‑peer transfers and other self‑custody mechanisms lack the intermediaries needed for mandatory reporting.

France has also seen a rise in physical attacks on crypto holders, with 36 incidents reported in the first eight months of 2026—a 64 % increase over the entire previous year. Leaked tax‑authority data has been cited as a contributing factor.