DAC8: the EU tax reporting obligation for crypto providers
From 2026, EU CASPs must report extensive tax data about their customers to tax authorities. What exactly does DAC8 require — and what does this mean for tax investigators?
The 8th amendment of the EU Directive on Administrative Cooperation (DAC8) is a relatively low-profile piece of legislation that will put European crypto providers in front of what is likely to be their largest reporting task in 2026. At its core, the idea is simple: if customers earn gains through crypto-assets, tax authorities should know about them — similar to how classical bank accounts are treated under the OECD-CRS (Common Reporting Standard).
What must CASPs report from 2026?
From tax year 2026 (reporting deadlines starting in 2027), Crypto-Asset Service Providers must transmit the following information on each reportable customer to the tax authority of the customer's country of residence:
- Customer identity (name, date of birth, tax identification number, residence)
- Annual turnover by asset category — purchases, sales, exchanges
- Aggregated gross proceeds from disposals
- Transfers between self-custodied wallets and CASP accounts
The data is transmitted through the existing EU mutual-assistance network and exchanged internationally between EU states.
What DAC8 means for tax investigators
So far, it has been cumbersome for tax offices to audit Bitcoin-related capital gains. Self-declarations were the primary instrument, field audits a rare tool. With DAC8, this changes fundamentally:
- Cross-check datasets — Tax offices can reconcile self-declarations with CASP filings.
- Cross-border cooperation — A German taxpayer with a Binance (Malta) account will become visible in Germany.
- Transfers to self-custody — CASPs must report when customers move coins into their own wallets. This is where blockchain forensics comes in.
The bridge to on-chain analysis
DAC8 captures everything that passes through a CASP. Everything beyond that — self-custodied wallets, DeFi, peer-to-peer — remains the terrain of on-chain forensics. A typical scenario:
A taxpayer sells 5 BTC on Kraken in 2026 (CASP report available). The tax office checks the holding period. The taxpayer claims to have held the coins since 2019. Coinator reconstructs the actual wallet history and shows: the coins arrived from another exchange in 2024.
At this moment, DAC8 and forensic analysis complement each other perfectly: DAC8 provides the entry point, Coinator the story behind it.
Our recommendation
Tax offices preparing for DAC8 data should in parallel build digital forensic competence. The combination of CASP reporting plus on-chain-based verification is, in many cases, the only way to reliably verify holding periods and source of funds.
We offer dedicated training and advisory services for tax authorities. Details on our about page.