Form 721: Declaring Your Cryptocurrency at Foreign Exchanges as a Spanish Tax Resident

Form 721 (Modelo 721), introduced by Orden HFP/887/2023, is the informative declaration on virtual currency assets held at crypto-asset service providers (CASPs) established outside Spain, mandatory for Spanish tax residents from the 2023 tax year. The filing threshold is €50,000 — but unlike Form 720's per-block threshold, the €50,000 limit for Form 721 is a single combined figure across all crypto assets at all foreign platforms. The filing window is 1 January to 31 March. The declaration covers cryptocurrencies (Bitcoin, Ethereum, and others), stablecoins, utility tokens, and NFTs with economic value held at custodial platforms — it does not apply to self-custody wallets (Ledger, Trezor, MetaMask used non-custodially). From 1 January 2026, DAC8 (Directive 2023/2226/EU) will require EU-registered CASPs to automatically report Spanish tax resident users' account and transaction data to the AEAT, fundamentally changing the information available to Spanish tax authorities on cryptocurrency holdings.

We manage Form 721 compliance for Spanish tax residents with cryptocurrency at foreign exchanges, from filing obligation determination and annual return preparation through IRPF consistency review and DAC8 readiness preparation.

Why Form 721 Catches Cryptocurrency Holders Who Think Their Obligations End with Their IRPF Return

Most cryptocurrency holders who are aware of their tax obligations in Spain focus on the IRPF: declaring gains from disposals (selling, converting to another crypto, using crypto to pay for goods or services) in the savings income section of the annual return. This is correct — but it is not sufficient.

Form 721 is a separate informative declaration that exists independently of the IRPF. Its purpose is to inform the AEAT of the total value of crypto holdings at foreign platforms as at 31 December — regardless of whether any taxable event occurred during the year. A taxpayer who holds Bitcoin at Coinbase and never sold it during the year has no IRPF crypto liability but does have a Form 721 obligation if the total value exceeds €50,000.

The combined threshold is a common trap. A taxpayer with €20,000 on Binance, €15,000 on Kraken, and €18,000 on Coinbase OX has a total of €53,000 across three platforms — above the €50,000 threshold — despite no individual platform exceeding €50,000. The entire portfolio must be declared on Form 721.

Our Service for Form 721 Cryptocurrency Overseas Assets Declaration

We begin with a complete portfolio snapshot: all foreign exchange and custodial accounts, all asset types (spot holdings, staked assets, yield-bearing positions, locked liquidity), and the 31 December market values. We apply the €50,000 combined threshold and determine whether a filing obligation exists.

For the annual Form 721, we prepare and file electronically within the 1 January–31 March window. We coordinate the Form 721 holdings data with the IRPF return for the same year to ensure consistency: the balance declared on Form 721 should be reconcilable with the opening balance, disposals declared in IRPF, new acquisitions, and closing balance.

For DAC8 readiness, we review the client’s complete historic IRPF and Form 721 compliance and identify any positions that could generate a data mismatch when EU CASPs begin automatic reporting in 2026. We manage voluntary regularisation for any historic gaps before the automatic reporting begins.

Regulatory Framework: Orden HFP/887/2023 (Form 721) and DAC8 (Directive 2023/2226/EU) from 2026

Orden HFP/887/2023 (9 August 2023) established Form 721, defined the covered assets, the €50,000 combined threshold, and the annual filing window. DAC8 (Council Directive 2023/2226/EU) of 17 October 2023 establishes the automatic reporting obligation for CASPs from 1 January 2026. Modelos 172 and 173 cover virtual currency operations and balances at Spanish-established CASPs — Form 721 specifically covers foreign CASPs. The IRPF treatment of crypto is governed by Ley 35/2006 (LIRPF) and the Consulta Vinculante criteria of the DGT on the classification of crypto gains as capital gains (transmissions) or ordinary income (mining, staking where there is no risk).

Real Results in Form 721 Crypto Overseas Declaration Compliance

• Form 721 filing for Spanish tax residents with holdings across multiple foreign exchanges (Binance, Kraken, Coinbase, OKX, Bybit, and others), correctly aggregating the combined threshold.
• IRPF consistency reviews identifying crypto taxable events missing from annual returns, managed through voluntary regularisation before AEAT review.
• DAC8 readiness assessments and historic compliance clean-ups for clients anticipating auto-reporting from 2026.
• Coordination of Form 720 (traditional overseas assets) and Form 721 (crypto overseas) for clients with both types of overseas holding.
• Self-custody wallet exclusion analysis confirming that hardware wallet holdings correctly fall outside the Form 721 obligation.