Can the Tax Authorities investigate you for cryptocurrencies? Warning signs

The short answer is: yes, it can, and it is doing so with increasing frequency and sophistication. Understanding what triggers investigations helps you maintain a solid tax position.

AEAT's sources of information on crypto

Forms 172 and 173

Since 2023, all exchanges operating in Spain are mandatory reporters to the AEAT regarding their users' balances (172) and the operations carried out (173). The AEAT cross-references this data with your IRPF.

Form 721

The declaration of cryptocurrencies in foreign exchanges that exceed €50,000 allows the AEAT to have a map of offshore assets.

DAC8 (from 2026)

Automatic exchange of data with all EU countries. European exchanges will automatically report the operations of Spanish taxpayers.

Blockchain analytics

The AEAT has blockchain analysis tools (Chainalysis, Elliptic, or equivalent) to track public on-chain transactions, especially for wallets associated with verified accounts on exchanges.

Warning signs that attract inspections

1. Large discrepancy between the assets declared in IRPF/IP and the balances reported by exchanges in Form 172.
2. Omitted capital gains: if the exchange reported €200,000 in closed operations with a profit and your IRPF does not reflect them.
3. Inconsistent bank flows: deposits into accounts coming from exchanges or P2P without justification in the tax return.
4. Failure to file Form 720/721 while holding foreign assets above the threshold.
5. Sudden change in wealth not justified by declared income.
6. Third-party reports (ex-partners, former employees…).

What can the AEAT do?

1. Information request: they ask you to justify certain transactions or provide additional documentation.
2. Limited verification: a review of a specific element of the tax return.
3. Full inspection: an exhaustive investigation of several fiscal years.
4. Settlement notice with penalty: if intentional concealment is detected, the penalty can reach 150% of the defrauded amount, in addition to late payment interest.

Statute of limitations: 4 years (or 10 in serious cases)

In general, the AEAT can investigate the last 4 years. However, if there is fraud or concealment, the period is extended up to 10 years.

How to protect yourself

1. Always declare, even if you are not sure of the exact amount. An incorrect declaration is less serious than an omission.
2. Keep all documentation for at least 10 years.
3. Do not make manual adjustments without documentary support.
4. Voluntarily regularize if you have committed errors in previous years (this significantly reduces penalties).

Conclusion

The AEAT does not inspect at random; it uses risk algorithms that cross-reference multiple data sources. If your declarations are consistent with the information they already have, the risk of inspection is minimal. If there are discrepancies, it is only a matter of time.