In the field of succession law, the distinction between donatio mortis causa and inter vivos donations is crucial for ensuring efficient estate planning and avoiding tax issues. As professionals, we understand that the line separating these concepts can be blurred, which creates challenges for both lawyers and notaries responsible for their formalization. In this article, we will analyze the distinctive characteristics of each figure, their tax treatment under the Impuesto sobre Sucesiones y Donaciones (ISD), and the practical problems that arise in the qualification of these acts.
Donatio mortis causa: characteristics and treatment
Donatio mortis causa is characterized by being an act that only produces effects after the death of the donor, once the testamentary formalities have been fulfilled. According to Article 620 of the Civil Code (CC), it is assimilated to a legacy, which implies that it must comply with the same formalities as a will. This figure allows the donor to dispose of their assets free of charge, but conditioned upon their death, being revocable until that moment.
From a fiscal perspective, donaciones mortis causa are treated as acquisitions by succession, meaning they are taxed under the succession regime of the ISD. This can be advantageous compared to inter vivos donations, especially in autonomous communities with significant bonuses in the succession tax bracket. However, the lack of clarity in the distinction between donatio mortis causa and succession agreements, particularly in regions with foral law, can complicate their tax treatment.
Inter vivos donation: usufruct reservation and tax considerations
Inter vivos donations, primarily regulated by Article 618 of the CC, are current acts of disposition that transfer ownership of assets immediately, although the donor may reserve usufruct. This usufruct reservation is common in donations to descendants, allowing the donor to continue enjoying the assets while alive.
From a tax perspective, inter vivos donations are taxed as such under the ISD, generally at higher rates than successions. However, estate planning can take advantage of reductions based on kinship and possible regional bonuses, although the latter are often less generous than in the succession context. The correct qualification of the act at the time of its formalization is essential to avoid unwanted tax contingencies.
Delivery upon death and legacy: key differences
Delivery upon death, implicitly regulated in Article 620 CC, resembles donatio mortis causa, but with the peculiarity that it does not require strict testamentary formalities. In practice, this figure is used to bequeath specific assets without constituting a formal legacy, which can facilitate transmission in certain circumstances.
The legacy, on the other hand, is a specific testamentary disposition that grants concrete assets to a particular person. Unlike donatio mortis causa, the legacy always requires a formal will and is incorporated into the hereditary estate at the time of the succession opening. The jurisprudence of the Supreme Court, as seen in STS 729/2022, has emphasized the importance of distinguishing these figures to avoid defects in the qualification of the act and its tax treatment.
Practical challenges in notarial qualification
In our daily practice, one of the greatest challenges is the correct qualification of donations, especially when combining inter vivos and mortis causa elements. Confusion often arises in the drafting of notarial deeds that do not clearly define the nature of the act, which can lead to disputes among heirs and unforeseen tax contingencies.
A common issue is the interpretation of the donor's intent when clauses are included that condition the delivery of assets upon the donor's death, but without following testamentary formalities. In these cases, the qualification as donatio mortis causa may be questioned, affecting its treatment under the ISD and the validity of the act itself, as noted by the General Directorate of Taxes in several recent consultations from 2025.
- Clearly define the type of donation in the notarial deed.
- Ensure compliance with testamentary formalities if a mortis causa effect is intended.
- Consult regional regulations to take advantage of specific tax bonuses.
Conclusion
A correct understanding and application of donaciones mortis causa and inter vivos is essential to ensure effective succession planning. Legal professionals must be meticulous in the qualification of these acts, ensuring compliance with legal formalities and taking advantage of available tax benefits. Tools like LexPartis allow us to manage these processes with greater rigor and efficiency, ensuring that our clients obtain the maximum benefit from their testamentary dispositions.