How far back can I file the Modelo 210 retrospectively?

Within the four-year statute of limitations, the Modelo 210 can be filed retrospectively at any time. The limitation period begins on the day after the statutory due date. For imputed income for the 2021 tax year (due 31 December 2022), the limitation expires on 31 December 2026. For rental income for the 2021 tax year (due 20 January 2022), the limitation expires on 20 January 2026. Differentiated by income type: Self-use/vacant: tax year 2022 expires on 31 December 2026 (due date was 31 December 2023, plus 4 years). Rental income: tax year 2022 expires on 20 January 2027 (due date was 20 January 2023, plus 4 years). In 2026, tax years 2022 to 2025 can accordingly still be filed. For 2021, the window has either closed or is about to, depending on income type. Voluntary late filing incurs surcharges under Article 27 LGT — but no penalties. This is the critical distinction: someone who acts on their own initiative pays a maximum surcharge of 15% plus late-payment interest. Someone who waits for the AEAT to act risks penalties of 50% to 150% of the tax due under Article 191 LGT. The AEAT has access to cadastral data and land registry records and can link property ownership to non-residents. Automatic information exchange with most EU member states and many third countries — including the UK, the US and Switzerland — makes identification technically possible. The risk is real, even if audit frequency for small liabilities may be lower. From a strategic standpoint, owners who have not filed for several years should approach the catch-up in a structured way. This means filing all outstanding years in a single batch, factoring in the surcharges, and paying the total in one go. An experienced Gestor or Asesor Fiscal can process the outstanding returns efficiently and calculate the surcharges in advance. A common trigger for retrospective filings: the owner wants to sell their Spanish property and the notary or buyer asks for proof of tax compliance. Outstanding returns can delay or complicate the sale process. For tax years from 2026, the due dates — and consequently the limitation periods — shift in accordance with the Orden HAC/623/2026.