Modelo 721: how to report crypto held abroad in Spain

What is Modelo 721? The short answer

Modelo 721 (Form 721) is the information return in which Spanish tax residents report crypto held for them by a platform abroad, if it is worth more than €50,000 in total on 31 December. You file it between 1 January and 31 March. No tax is paid with it, and your own wallet does not count.

Form 721 was created by Law 11/2021 on tax fraud, which added virtual currencies to the eighteenth additional provision of the General Tax Law (Ley General Tributaria), the same provision behind Modelo 720. The detail is in article 42 quater of the tax management and inspection regulation, and the form was approved by Order HFP/886/2023. The first return covered the 2023 tax year and was filed in 2024.

Who has to file Modelo 721?

Under article 42 quater, it is filed by individuals and companies resident in Spain, permanent establishments of non-residents and entities without legal personality, such as undivided estates and co-ownerships. You do not have to be the holder: authorised persons, beneficiaries, anyone with power of disposal and the beneficial owner also report, for example for crypto held in the name of a company or trust set up outside Spain.

The obligation arises when the total value of that crypto on 31 December exceeds €50,000. If you are over the limit, you report all of it, not just the part above the threshold. Resident companies, and business owners who keep accounts under the Spanish Commercial Code, are exempt as long as they record each coin individually with its name, value, custodian and country.

Two cases that often raise questions, according to the AEAT's FAQ on Form 721: residents of the Basque Country and Navarre also file, under the state or regional (foral) rules that apply to them; and heirs report from the moment they accept the inheritance. The FAQ does not cover people taxed under the inbound workers' regime (the Beckham Law), so if that is you, confirm your position before you stop filing. And if you are not sure you are resident, start with the guide to Spanish tax residency.

When is your crypto "abroad"?

This is where many guides go wrong. The AEAT requires two conditions together: the coins must be held by a third party that safeguards private keys for its customers, and that third party must be neither resident in Spain nor a permanent establishment here. The rule puts it this way: crypto is abroad when its custodian does not have to file Form 172, the balance report that the thirteenth additional provision of the income tax law imposes on resident custodians.

On self-custody, the AEAT is clear: whether the wallet is cold or hot, coins whose keys you control are not added to the balance and are not reported on Form 721. To check where a provider is registered, the AEAT itself points to the Banco de España register of exchange and custody providers.

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When is it filed, and when do you have to file again?

Article 4 of Order HFP/886/2023 sets the window: from 1 January to 31 March of the following year. Crypto you hold on 31 December 2026 is reported between 1 January and 31 March 2027.

You do not file every year. After your first return, article 42 quater.6 only requires you to file again in two cases:

1. If your total balance rises by more than €20,000 compared with the balance that triggered your last return. You compare with what you last filed, not with the previous year.
2. If you stop holding coins you had already reported, through a sale, a transfer or death. You then report the balance on the date you stopped holding them. There is one exception: if you sell and reinvest the whole amount in other crypto abroad that you also report, you only report the 31 December balances.

The AEAT adds that a coin bought and sold within the same year, and never reported, does not need an exit entry, and that if the person who filed Form 721 dies, the undivided estate or the heirs must report that exit.

What does Modelo 721 ask for, and how is crypto valued?

Article 42 quater.3 asks for three blocks of information:

• The custodian: name or company name, tax ID in its country, address or website.
• Each coin: its full identification. The AEAT asks for the name and ticker as they appear on the reference price-tracking sites, such as Bitcoin (BTC) or Ethereum (ETH).
• The balance: units of each coin on 31 December and their value in euros.

To value them, you take the 31 December price from the main trading platforms or price-tracking websites. If a coin has no price, you give a reasonable estimate of its market value. Either way, you must state which price or value you used. Each coin goes in its own record: balances are not aggregated. Form 721 can only be filed online, on the AEAT's electronic portal (sede electrónica), with the web form or, for large portfolios, an XML message.

What is the fine for not filing Modelo 721?

The fines you still see on many websites (€5,000 per item, with a minimum of €10,000) no longer exist. After the CJEU judgment of 27 January 2022 (case C-788/19) on Modelo 720, Law 5/2022 rewrote the eighteenth additional provision without a penalty regime of its own. Since then the general articles of the General Tax Law apply:

For counting, article 42 quater.7 treats the information on each custodian and the balance of each coin as a set of data, and the identification of each coin as an item.

The same law changed article 39 of the income tax law. Assets that do not match your declared income or wealth are still an unjustified capital gain (ganancia patrimonial no justificada), taxed in the general income base of the year they are discovered, but you can now avoid that if you prove you held them since before the limitation period. The serious risk is not the Form 721 fine but income tax or wealth tax returns that do not match it.

How does it relate to wealth tax, income tax and Modelo 720?

Form 721 does not assess any tax. It is the snapshot the AEAT uses to check the other two:

For wealth tax, the AEAT manual requires you to report the euro balance of each coin on the accrual date, 31 December, whether it sits on a foreign exchange, a Spanish one or your hardware wallet. How much you pay depends on your region (comunidad autónoma): see the guide to wealth tax by region.

For income tax, selling crypto for euros or swapping it for another coin produces a capital gain or loss. The AEAT income tax manual treats a crypto-to-crypto swap as an exchange of assets (permuta) and applies FIFO: the coins you bought first are treated as sold first. Those gains are taxed in the savings income base at 19% to 30%, adding the state and regional scales in articles 66 and 76 of the income tax law.

Modelo 720 covers three other categories abroad: accounts, securities and insurance, and real estate. Each block has its own €50,000 threshold, the same window and the same €20,000 rule. Crypto goes on Form 721, not Form 720. If you have just arrived, the guide to taxes when moving to Spain puts all these obligations in order.

Illustrative example: Javier, €180,000 on a foreign exchange and a hardware wallet

Javier is 49, lives in Málaga and sold his stake in a software company in 2022. His net wealth is around €3 million. On 31 December 2026 he holds crypto in three places:

Step 1. Separate what goes on Form 721. Only the €180,000 on the foreign exchange. The €95,000 in his hardware wallet and the €20,000 with the Spanish custodian stay out.

Step 2. Check the threshold. €180,000 is above €50,000, so he must report all three coins on the exchange, each in its own record.

Step 3. Compare with the last Form 721, not the previous year. Javier filed Form 721 for 2024 with €150,000. On 31 December 2025 he had €162,000: €12,000 more, below €20,000, so he did not file for 2025. Now he has €180,000: only €18,000 more than in 2025, but €30,000 more than his last return. As that exceeds €20,000, he files Form 721 for 2026 between 1 January and 31 March 2027.

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Step 4. Work out what he risks by not filing. With one custodian and three coins, his return has seven items or sets of data: one for the custodian, three balances and three coin identifications. At €20 each that is €140, below the minimum, so the fine would be €300, or €150 if he filed late before Hacienda asked him to.

Step 5. Reconcile wealth tax and income tax. On his 2026 wealth tax return, filed in 2027, he reports the full €295,000, hardware wallet included. And if he swapped ETH for USDC during 2026, that swap is a gain or loss on his 2026 income tax return, even though the money never left the exchange.

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What changes with DAC8 from 2026?

DAC8 is Directive (EU) 2023/2226 of 17 October 2023. It extends the automatic exchange of tax information to crypto-assets: crypto-asset service providers must establish their customers' tax residence and report their transactions, and tax authorities pass that data to each other. Member states had to transpose it by 31 December 2025 and apply it from 1 January 2026. Each year's data is exchanged within nine months of the year end, so data for 2026 will be shared by 30 September 2027 at the latest.

Spain did not make it in time. The government introduced its transposition bill (121/000060) on 5 June 2025, and the Congreso lists it as lapsed since 6 October 2026, the day the Spanish parliament (Cortes Generales) was dissolved. Bringing DAC8 into Spanish law will need a new bill in the next parliament.

In practice, for you:

• The 2026 Form 721 follows the same rules: Order HFP/886/2023 and article 42 quater, which refer to virtual currencies. It is filed between 1 January and 31 March 2027.
• DAC8 does not replace your filing. The provider reports, not you, and it does not release you from Form 721 or from declaring your gains.
• What you hold abroad will become more visible. Providers in other states that already apply DAC8 will report under their own rules. It makes sense for your Form 721, wealth tax and income tax returns to tell the same story as that data.

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Common mistakes with Modelo 721

• Comparing with the previous year. The €20,000 rule is measured against the balance on the last Form 721 you filed. Like Javier, you can rise by less than €20,000 in a year and still have to file.
• Judging by the brand or the website language. What decides is whether the entity holding your keys is resident or has a permanent establishment in Spain and files Form 172.
• Thinking the hardware wallet disappears. It stays off Form 721, but it goes on your wealth tax return, and its sales and swaps are taxed on your income tax return.
• Forgetting exits. If you sold all the coins you had reported, you must file that year even if your final balance is below €50,000.
• Valuing at an average price. The rule requires the 31 December price and that you state which one you used.
• Relying on the old fines. Neither the €5,000 per item nor the rule that taxed undeclared assets with no time limit still applies, but Form 721 is still mandatory and the AEAT checks it against your income tax return.

How Melso helps

Melso Private offers lawful tax planning for people with net wealth from €1 million. Tax advisers work with an AI that reads your statements and returns and cross-checks each country's rules; they review each scenario, choose the measures and stand behind them. We file the returns we agree on, such as income tax, wealth tax and Forms 720 and 721, only after you approve the exact version. The first conversation lasts 45 minutes, is free of charge, and we reply within 2 business days: Request a conversation.

This article is for information only and does not replace professional advice for your case. Last reviewed: 18 October 2026.