Spain's tax agency warns of frequent errors in residents' income tax filings

Spain's tax authority cautions taxpayers that accepting the pre-filled draft of their income tax return without verification can lead to over‑payments, loss of deductions and trigger formal reviews. Common pitfalls include incorrect reporting of income, omitted regional deductions and errors in property or rental data, which may result in audits even long after the filing deadline.

For foreign‑resident taxpayers, the agency highlights that worldwide income—including foreign pensions, investment earnings, rental income and capital gains—must be declared, regardless of whether it was taxed abroad. Misunderstanding the €22,000 threshold, which applies only to earnings from a single Spanish employer, often leads residents to think they are exempt from filing when they are not. Overlooking foreign bank or broker statements, property sales abroad and the proper treatment of foreign pensions are among the frequent mistakes that can cause adjustments, penalties or administrative complications later.

Professional guidance is recommended to ensure all cross‑border income is correctly reported, avoid unnecessary revisions, and prevent potential penalties from the tax authority.