Declaring Crypto in France With an Accountant

The companion question to "can I self-file?" is "when should I not?" Most occasional investors can file themselves (see declare without an accountant). This guide is the honest decision boundary: the specific situations where an expert-comptable is worth the fee, what the cabinet actually does, and how the engagement is scoped in 2026.

TL;DR

• Self-file if you are a straightforward occasional investor with manageable activity.
• Use a cabinet if: professional/BNC risk, high volume/many chains, substantial staking/DeFi (BNC), prior unreported years, exit/residency question, or a company holding crypto (FEC).
• The cabinet reconstructs/reconciles, classifies (PFU vs BNC), prepares 2086/3916-bis/2042 C (or BNC/déclaration contrôlée/FEC), documents the position, and runs the DAC8 reconciliation.
• Pricing: scoped to complexity (volume, chains, DeFi, company), not asset value.
• DAC8 from 2026 adds a reconciliation step the cabinet operationalises — it does not disappear.

When the expert-comptable is worth it

The decision is not "rich vs not" — it is complexity and risk. Engage a cabinet when any of these is true:

If none apply, self-filing is appropriate and the cabinet fee is avoidable. The error in both directions is real: self-filing a professional/BNC position botches it; paying a cabinet for a two-disposal occasional year over-spends.

What the cabinet actually does

A French crypto engagement is not "fill in the form." It is:

1. Reconstruct and reconcile the full multi-year, multi-chain history.
2. Classify: occasional (PFU/150 VH bis) vs professional (BNC) vs reward income (BNC at receipt).
3. Compute: gains under article 150 VH bis; reward income under BNC; losses (intra-year, see loss treatment).
4. Prepare: Form 2086, 3916-bis, carry to 2042 C — or the BNC declaration / déclaration contrôlée and FEC for a company.
5. Document the occasional/professional position (the audit-defence file).
6. Reconcile against DAC8-reported data (from 2026) and investigate material discrepancies.

Step 5 and step 6 are where the cabinet's value over a tool is clearest — the judgement and the documented defence, not the arithmetic.

How the engagement is scoped and priced

Pricing tracks complexity, not asset value:

• One-off: history reconstruction (often multi-year) — usually the largest cost.
• Recurring annual: the return (2086/3916-bis/2042 C or BNC/FEC) + the new DAC8 reconciliation step.
• Drivers: transaction volume, number of wallets/chains, DeFi/LP/staking complexity, company-vs-individual.

A flat "crypto return" fee that ignores volume and DeFi complexity underprices the work and absorbs the professional risk for free — expect a scoped quote.

Prior unreported years: the regularisation case

The clearest "use a cabinet/lawyer" case is prior unreported years. Given the 10-year reassessment window for omitted activity/accounts and DAC8 detection from 2026 (see DGFiP audit), a voluntary déclaration rectificative before the first DAC8 cross-check generally yields a materially better outcome than a discovered omission. This is national-tax-law work — not a self-filing or tool task.

DAC8 makes the cabinet step heavier, not optional

From 2026 the DGFiP receives CASP-reported data automatically. The cabinet's workflow gains a mandatory reconciliation step: client books vs reported data, investigate material discrepancies against a documented (firm-set) threshold, record it in the client file. Using a cabinet means this is done and documented properly — it does not remove the duty (see DAC8 for accounting firms for the practice-side view).

Practical guidance

1. Run the decision table — if any high-risk row applies, engage a cabinet.
2. Expect a scoped quote (volume/chains/DeFi/company), not a flat fee.
3. Bring a clean history — a reconstructable record lowers the cabinet's cost and your risk.
4. Regularise prior years with counsel ahead of the DAC8 cross-check.
5. Confirm the cabinet runs the DAC8 reconciliation and documents it.

How vendor tools fit alongside a cabinet

Waltio (French-specialised) and Koinly produce the 150 VH bis figures the cabinet validates and builds on — tools and cabinet are complementary, not alternatives. The tool does the arithmetic and history; the cabinet does the classification judgement, the documented defence, and the DAC8 reconciliation.

How Wag3s helps

Wag3s Folio gives the cabinet (and the client) a continuously reconcilable multi-chain history with 150 VH bis figures and listed foreign accounts; for company clients, Wag3s Ledger provides FEC-ready records — lowering the cabinet's reconstruction cost and supporting the DAC8 reconciliation. See the Folio and Ledger pages, and the Wag3s for accountants page.

Further reading

• Declare Crypto Without an Accountant (France) — the self-file counterpart
• France Crypto Tax Guide 2026
• Occasional vs Habitual Trader (France)
• BNC vs PFU for Crypto in France
• DGFiP Crypto Tax Audit
• DAC8 for Accounting Firms

Sources

• BNC/PFU boundary and the FEC requirement (article 150 VH bis CGI; BNC article 92 CGI) — Légifrance
• DGFiP — cabinet DAC8 reconciliation expectation from 2026
• Council Directive (EU) 2023/2226 (DAC8) — EUR-Lex