Choose the right procedure
Modelo 721 is an information return for qualifying virtual currencies held with foreign custodians. It is separate from Modelo 720 and from reporting taxable gains or wealth. The custody arrangement matters: holdings whose private keys you control yourself fall outside this specific custody-based reporting rule. That does not remove other tax obligations.
What to prepare
Identify the legal custodian and its tax residence, each currency, your role, units and euro valuation at the relevant date. Do not judge custody location solely from a website domain. Keep year-end statements and records of any reportable ending of ownership or authority. Never provide seed phrases or private keys to Newcomer or attach them to a tax return.
Spanish fields explained
Ejercicio is the reporting year. Identify each currency and custodian with the required units, euro balance and dates. The general year-end reporting exemption applies where the combined relevant balance does not exceed €50,000. After a first return, an increase above €20,000 compared with the last reported balance and certain previously reportable holdings that end require separate checks. Read the official exceptions before deciding.
How to submit
Use the AEAT Modelo 721 web form for the correct year with an accepted identity method or authorised representative. Check validation messages, review all records and complete the official signature and submission yourself. The regular filing period is 1 January to 31 March of the following year. Check the official calendar and any applicable technical-incident instructions.
After submission
Download the filed return and official receipt, and retain the valuation records. A saved draft is not a filing receipt. If records are wrong, use the official consultation/modification service for filed returns and follow its correction instructions. Filing 721 does not replace income-tax or wealth-tax reporting of those assets where applicable.