What happens if I do not file the Modelo 210?

The consequences depend on whether the AEAT discovers the omission and how much time has passed since the filing deadline. If the return is filed late but voluntarily — before the AEAT has initiated any action — surcharges apply under Article 27 of the Ley General Tributaria (LGT) in its current form: 1% per month of delay for the first twelve months, then a fixed surcharge of 15% plus late-payment interest (intereses de demora) from month thirteen onwards. For a tax liability of €500, filing six months late adds €30 in surcharges. Filing eighteen months late adds €75 plus accrued interest. If the AEAT itself identifies the non-filing, the penalties escalate significantly. Article 191 LGT provides for sanctions starting at 50% of the unpaid tax for minor negligence. In cases of serious negligence or deliberate evasion, the penalty can reach 150% of the tax due — on top of late-payment interest. The AEAT has substantial means of detection. It holds land registry and cadastral data linking properties to their owners, and participates in international tax information exchange with most EU member states and many third countries, including the United Kingdom (under the post-Brexit framework), the United States (via FATCA and the CRS), and Switzerland (via the CRS since 2018). The technical capacity to match foreign property owners against filed returns exists. The statute of limitations is four years from the date the tax fell due. After that, the AEAT can no longer pursue the claim. A practical consideration for owners who have not filed for several years: voluntary disclosure is significantly cheaper than waiting for the AEAT to act. The surcharges for spontaneous late filing under Article 27 are a fraction of the penalties under Article 191. A structured catch-up — filing the outstanding years in sequence — is standard practice and something any experienced Gestor or Asesor Fiscal can handle efficiently.