Modelo 720, 721 and the informative filings expats forget

Modelo 720 and 721 don't calculate any tax owed. That's exactly why expats forget them — they feel optional in a way that income tax forms don't. They aren't optional, and the penalty structure for missing them is disproportionate to almost any other filing in the Spanish system.

Modelo 720: foreign assets over €50,000

Spanish tax residents must declare foreign bank accounts, securities, and real estate if any single category exceeds €50,000 in value, by March 31 following the tax year. After the EU ruled the original penalty regime disproportionate in 2022, fines were reduced — but they're still real, and late filing without a reasonable-cause argument still carries meaningful risk.

Modelo 721: the newer crypto equivalent

Introduced for crypto assets held on foreign exchanges above €50,000, Modelo 721 catches expats who assume their crypto holdings are invisible to Spanish authorities because the exchange isn't Spanish. It isn't invisible, and the filing deadline mirrors 720.

The trap: you only file once, then only on change

After the initial declaration, you don't need to refile every year — only if a declared asset increases by more than €20,000, or a new asset crosses the threshold. This is precisely where people lose track: the absence of an annual reminder means the follow-up filing, when it's actually required, gets missed years later.