Guide

The Six-Month Deadline: How to Avoid Inheritance Tax Surcharges in Spain

Published April 2025 · 10 min read · By International Inheritance Spain

One of the most frequent and costly mistakes made by international heirs dealing with a Spanish estate is missing Spain's six-month inheritance tax deadline. The deadline is strict, automatic surcharges apply, and interest compounds on unpaid amounts. This guide explains everything you need to know.

The Legal Basis of the Deadline

Article 67 of the Spanish Inheritance and Gift Tax Law (Ley 29/1987 del Impuesto sobre Sucesiones y Donaciones) establishes that the inheritance tax return must be filed and the tax paid within six calendar months from the date of death.

This deadline applies to all heirs regardless of where they live — whether in London, Amsterdam, New York or Sydney. It applies whether the estate is large or small, whether there is a will or not, and whether the inheritance is accepted or not.

The Surcharges: Exact Amounts

Article 27 of the General Tax Law (Ley General Tributaria) establishes the surcharge regime for late filings:

• 5% surcharge: Filed between 6 and 12 months after the deadline
• 10% surcharge: Filed between 12 and 18 months after the deadline
• 15% surcharge: Filed between 18 and 24 months after the deadline
• 20% surcharge + interest: Filed more than 24 months after the deadline — plus statutory interest at the annual legal interest rate (currently 4.0625%)

These surcharges are applied on the tax that was due, not on the estate value. If you should have paid €20,000 in Spanish inheritance tax within six months, a 20% surcharge means an additional €4,000 — plus interest accruing from month 7.

When Does the Six Months Start?

The six-month period begins on the date of death — not the date you became aware of the death, not the date probate was opened, not the date you instructed a lawyer. The date of death, full stop.

This catches many international heirs by surprise, particularly when:

• The death occurred in Spain and the family in the UK was not notified immediately
• A UK or foreign probate process was started first and consumed months before anyone addressed the Spanish assets
• The heirs assumed the Spanish process could wait until the UK estate was settled
• Nobody knew there were Spanish assets until months after the death

The Extension: How to Get More Time

A six-month extension can be requested under Article 68 of the Inheritance Tax Regulation. The request must be:

• Submitted within the first five months from the date of death (not in month six)
• Made on Form 650 or by separate written request to the regional tax authority (Consejería de Hacienda)
• Accompanied by basic documentation identifying the heirs and the estate

If the extension is granted, the total deadline becomes 12 months from the date of death. Tax is not due at the time of the extension request — but it must be paid when the extended deadline expires.

Important: The extension is not guaranteed. It is granted administratively but can theoretically be refused. We routinely obtain extensions for our clients where more time is needed.

What Happens If the Tax Is Not Paid But Is Filed?

Filing the inheritance tax return on time but not paying immediately is possible in limited circumstances. Spain allows payment in instalments (fraccionamiento — up to 12 monthly instalments with guarantees) or deferred payment for the portion of the inheritance tax attributable to illiquid assets. This requires a formal application and guarantees.

What If You Did Not Know About the Estate?

If you genuinely did not know that the deceased had Spanish assets, you still owe the tax. However, the surcharge regime (not the penalty regime) applies only to voluntary late filings. If the tax authority discovers the undisclosed estate first, it may impose penalties of 50%–150% of the tax owed rather than the softer surcharge regime. This is a strong incentive to file, even late, before the tax authority finds out.

Contact Us Immediately — Every Day Counts

Our experience is that the most stressful cases are those where heirs contact us in month five or six. In those cases, we work intensively and almost always succeed in meeting the deadline — but it requires everyone to move very quickly. If you contact us in months one or two, the process is far smoother, and we can plan properly.