Spain's 2025 tax filing season warns of common mistakes

The 2025 Spanish income‑tax campaign is approaching its deadline of 30 June 2026, prompting tax advisers to caution millions of contributors against accepting the tax authority’s draft return without thorough verification. Experts such as Rogelio Villalba and Laura Encina highlight four recurrent errors that inflate tax bills: confirming the draft without review, overlooking regional (autonomous‑community) deductions, failing to retain receipts needed for expense deductions, and delaying fiscal planning until after the year‑end window.

In the Basque province of Bizkaia, the guidance is similar but stresses the particular foral deductions available for housing, family, and work‑related expenses. Taxpayers are urged to update personal data, gather income certificates, and check each line of the draft to avoid missing deductions that could significantly affect the refund or amount owed. Early preparation and careful document review are presented as the most effective ways to prevent costly errors.

The combined advice across the country underlines that diligent review of the draft return and proper documentation can safeguard taxpayers from unnecessary payments and ensure they claim all entitled benefits.