Expert Legal Services for International Succession Cases: Spanish Inheritance Law and Affidavits

At Costaluz Lawyers, we understand the complexities of international succession and inheritance cases. If you are navigating an inheritance issue that involves Spanish assets or requires the validation of Spanish law, our team of expert lawyers is here to provide you with clear, professional support. One of the essential services we offer is the preparation of a formal Affidavit of Spanish Law for submission to probate courts worldwide.

Important: Spanish succession follows two distinct paths depending on whether the deceased left a valid will (testate) or not (intestate). The intestate path requires a Declaration of Intestate Heirs (Declaración de Herederos Abintestato) — a step not needed when a will exists. Learn more about the succession process →

What is an Affidavit of Spanish Law?

An Affidavit of Spanish Law is a legal declaration that explains how Spanish law applies to a specific inheritance case. It is a crucial document when dealing with cross-border legal proceedings, especially in probate courts that need clarity on Spanish inheritance laws. This affidavit ensures that Spanish law is correctly understood and applied in the jurisdiction where the case is being heard.

Why Choose Costaluz Lawyers?

1. International Expertise
   Our team is composed of experienced lawyers specializing in both international law and Spanish legislation. We have a strong track record of working with probate courts globally, ensuring that Spanish law is correctly applied and understood in various jurisdictions.
2. Tailored, Personalized Service
   Every inheritance case is unique. We ensure that each affidavit is specifically tailored to your case, fully aligned with international legal standards and requirements. You can be confident that the document will meet all the necessary criteria to be accepted by the relevant courts.
3. Clear, Transparent Guidance
   We pride ourselves on offering straightforward and transparent legal advice. Our goal is to guide you through every step of the process, ensuring that you fully understand the legal implications and your rights.
4. Expertise in Common Law-Civil Law Cross Cases
   Our expertise is particularly valuable in cases where there is an intersection between Common Law and Civil Law systems, especially when inheritance laws differ significantly between jurisdictions. We navigate these complexities to ensure that the resolution is both fair and legally sound.

How It Works:

1. Initial Consultation
   We begin by thoroughly reviewing your case and gathering all the necessary details to prepare a comprehensive affidavit.
2. Affidavit Preparation
   Our legal team drafts the affidavit, ensuring it precisely reflects the applicable Spanish inheritance laws, and is in line with international legal requirements.
3. Review and Signature
   We carefully review the affidavit to ensure its accuracy and legal soundness before having it signed by our expert lawyers.
4. Submission to Court
   Once prepared and signed, the affidavit is officially submitted to the probate court in your jurisdiction for validation.

When Might You Need an Affidavit of Spanish Law?

An Affidavit of Spanish Law may be required in various situations, including:

• Cross-Border Inheritances: If the estate or heirs are based in Spain but the probate court is in another country, an affidavit of Spanish law is necessary to explain how Spanish law applies to the inheritance matter. This ensures that the probate court understands the legal framework governing Spanish assets and the validity of the will executed in Spain.
• International Legal Disputes: In cases where there are legal disputes regarding the inheritance of Spanish assets, and the court needs clarity on how Spanish inheritance law affects the situation, the affidavit serves to confirm the correct legal procedure and rights of the beneficiaries under Spanish law.
• Multiple Jurisdictions Involved: When an individual has assets or heirs in different countries, and multiple legal systems are at play, an affidavit helps to determine how Spanish law intersects with the laws of other jurisdictions involved in the case. It can help clarify the applicable law and prevent conflicting interpretations.
• Probate Court Validation: If a probate court outside of Spain needs confirmation of the validity of a Spanish will, or if the court requires clarity on the application of Spanish inheritance law to assets located in Spain, an affidavit of Spanish law is essential to ensure that the Spanish will is properly recognized and enforced in that jurisdiction.
• Testamentary Formalities: If the probate court is uncertain about the formal validity of a will executed in Spain (for example, whether it was properly signed before a notary or whether the testator had the legal capacity to make the will), an affidavit will confirm that all necessary Spanish legal formalities were followed and that the will is valid under Spanish law.
• Legal Rights and Forced Heirship: In cases where there is a dispute over forced heirship (legítima) rights in Spain, particularly when the deceased’s will conflicts with mandatory inheritance provisions, an affidavit of Spanish law can clarify the extent of these rights and their implications under Spanish law, even if the heirs are governed by another legal system, such as in Common Law jurisdictions.
• Recognition of Foreign Wills: If a deceased person executed multiple wills in different jurisdictions, an affidavit may be required to explain how the Spanish will is treated in relation to any foreign wills and ensure that the Spanish will is followed for assets located in Spain.

In summary, an Affidavit of Spanish Law is critical whenever Spanish inheritance law needs to be clarified or applied in international legal proceedings, helping courts in different jurisdictions understand how to manage and distribute an estate with Spanish assets. This ensures the smooth and lawful administration of the estate across borders.

Why Costaluz Lawyers?

We make international legal processes seamless and manageable. Our goal is to ensure that your rights are protected in any jurisdiction, and all necessary legal documentation is in place. With our expert guidance, you can confidently move forward with your inheritance case, knowing that Spanish law is being applied correctly.

Contact us today to schedule a consultation and discuss how we can help with your international succession case and the preparation of your Affidavit of Spanish Law. Let us guide you through the complexities of inheritance law and ensure that your interests are upheld worldwide.

For a complete overview of wills and inheritance in Spain, see our Spanish Wills & Testament Guide 2026.

Reviewed by María Luisa de Castro, CEO at CostaLuz Lawyers — Updated 2026

This is general information, not definitive legal advice — every case requires individual analysis.