Crypto tax regularization: how to catch up with the Treasury

There are many crypto investors in Spain who, due to ignorance or the complexity of the declaration, have not declared their profits for years. If this is your case, you have options. Regularizing voluntarily is always better than waiting for the Treasury to find you.

Why regularize now?

The reasons not to wait any longer:

1. DAC8: From 2026, the Treasury will receive automatic information from European exchanges. If you have crypto in Coinbase EU, Kraken EU, Bitstamp... → The Treasury will know.
2. Model 172 already in force: Spanish exchanges have already been reporting since 2024.
3. Blockchain analytics: The AEAT uses Chainalysis and other tools.
4. Prescription: Debts expire after 4 years. A requirement before the prescription interrupts it.

The cost of waiting to be detected: Penalties of 50-150% of the amount defrauded + late payment interest. The cost of voluntarily regularizing is much lower.

Voluntary regularization: less penalty

If you declare spontaneously (without having received a prior request), surcharges are applied instead of sanctions:

Within the first year from the expiration of the term

• 5% surcharge: If you regularize it within 3 months following the deadline.
• 10% surcharge: Between 3 and 6 months after the deadline.
• 15% surcharge: Between 6 and 12 months later.
• 20% surcharge + interest: More than 12 months later.

There is no additional penalty in these cases (only the surcharge and interest in the last tranche).

Outside the recharge period

If more than 12 months have passed since the declaration deadline, you file a supplementary declaration. Treasury will apply:

• Default interest (currently ~4.0625% annually).
• No penalty if there has been no prior request and the error was involuntary.

Step by step: how to regularize

Step 1: Determine which years you have to regularize

The personal income tax expires after 4 years. In 2025 you can regularize:

• 2024 (non-prescribed fiscal year, current year).
• 2023 (not prescribed, expires in July 2028).
• 2022 (not prescribed, expires in July 2027).
• 2021 (not prescribed, expires in July 2026).
• 2020 and earlier → already prescribed if there is no prior requirement.

Exception: If the undeclared amount exceeds €120,000 in a financial year, there may be criminal liability with longer prescription periods.

Step 2: Collect the complete history

For each year, you need the trading history from the beginning (to correctly apply FIFO):

• If you bought Bitcoin in 2017 and sold in 2021, you need the 2017 purchase price.
• Export all exchange CSVs from all years.
• Rebuild on-chain history if necessary.

Step 3: Calculate the FIFO for each year

Recalculate the profits and losses for each year, in chronological order:

• The acquisition cost at the beginning of each year comes from the closing of the previous year.
• Use tools like Koinly with date ranges by year.

Step 4: Submit supplementary statements

For each year to be regularized:

• Access historical WEB income for that year.
• Submit a complementary statement with undeclared profits/losses.
• Pay the resulting fee + surcharge/interest.

Note: Returns from previous years are presented at the AEAT Electronic Headquarters using the service corresponding to each year.

Step 5: Also regularize Form 721 if applicable

If you had more than €50,000 in crypto in foreign exchanges in any of the years to be regularized, you must also present the omitted Forms 721 (or 720, as the case may be).

The Treasury is not going to forgive you alone: ​​wait for a request

If you decide not to regularize and wait for the Treasury to find you:

• You will receive a request for information (deadline to explain).
• If the inspection confirms the debt → settlement proposal.
• Penalty for minor infraction (concealment): 50% of the fee.
• Penalty for serious infringement (fraudulent means): up to 150%.
• Default interest accumulated since expiration.

Example: You did not declare €20,000 of profits in 2021 → you owe €3,800 fee + 50% penalty (€1,900) + interest (€600) = ~€6,300 total. If you had voluntarily regularized it in 2022 → only €3,800 + 15% surcharge = ~€4,370.

Strategy: using an advisor is essential

For regularization, you need a tax advisor specialized in crypto. Errors in calculating FIFO for multiple years are very common and can be very costly.

The advisor can:

• Calculate exactly what you owe (and what you don't owe).
• Prepare the complementary ones correctly.
• Negotiate with the Treasury if there is already a requirement (you can obtain a reduction in penalties).
• Guide you on whether it is advisable to regularize everything or only the most relevant years.

The good news

• The penalty is not catastrophic if you act voluntarily: Surcharges of 5-20% are manageable.
• Losses are also recovered: If in any year you had losses that you did not declare, when regularizing them you can deduct them from the years with profits.
• Tranquility has a value: Living with the worry of "will they discover me?" It has a real psychological cost. Regularize closes that chapter.

Updated: April 2026 | Fiscal year: 2021-2025