Don't let a simple mistake cost you: a guide to correcting common errors in your spanish tax return

As the 2026 Spanish tax campaign kicks off on April 8th, it's crucial to avoid common pitfalls that could lead to lost income.

Review your draft carefully before submission

The first step is accessing your preliminary tax return, a document prepared by the Spanish tax authority (Hacienda) to simplify the process. However, automatically submitting this draft without reviewing it is a critical mistake.

This is because Hacienda may have incorrect information due to outdated personal, family, or economic data. If your situation has changed, the tax authority might not be aware of it.

Key areas to double-check include personal and family details, work income, extra earnings, autonomous deductions, and tax benefits for contributions. Special attention should be given to boxes 435 and 460 of the Model 100 income tax return.

Understanding boxes 435 and 460

Box 435 represents the general definitive taxable base, which is the amount subject to the IRPF tax rates after subtracting reductions. It's calculated by adding net work income, property income (rents), business income, and certain non-capital gains.

Box 460, on the other hand, reflects the savings base, grouping returns from investments, such as interest, dividends, and the net balance of capital gains and losses during the period. It's essential to review this box as it affects the taxation of savings and certain deduction limits.

To avoid errors in your tax return, always access your draft in Renta Web, review it point by point, and edit any incorrect information. You can modify details such as salaries, pension amounts, or rental income. Save your changes and check the