The Inheritance and Gift Tax (ISD) is a tax that has generated significant attention both in academic circles and in professional practice. Based on Law 29/1987, its application varies considerably among autonomous communities, adding a layer of complexity to legal advice. In our daily practice, we find that professionals in inheritance law must be attentive not only to state regulations but also to regional particularities and jurisprudential interpretations that may influence the planning and management of inheritances.
The Taxable Event in the ISD
The taxable event of the ISD is defined in Article 3 of Law 29/1987, focusing on the acquisition of assets and rights through inheritance, legacy, or any other succession title. In this context, the notion of 'acquisition' is interpreted broadly, encompassing not only the actual transfers of property but also situations where legal availability materializes without the physical transfer of assets.
A crucial aspect is the distinction between inter vivos and mortis causa acquisitions, as the tax treatment differs significantly. In mortis causa acquisitions, the taxable event occurs at the moment of the decedent's death, which generates tax obligations that must be managed precisely to avoid penalties.
In our experience, a recurring source of controversy is the determination of the exact moment of tax accrual, especially in cases where the existence or validity of the will is disputed. The rulings of the DGT from 2025 have reinforced the criterion that accrual is fixed at the date of death, regardless of subsequent litigation over the inheritance.
Taxpayer and Tax Liability
The taxpayer of the ISD in mortis causa acquisitions is, according to Article 5 of Law 29/1987, the heir or legatee. The regulations require these taxpayers to declare and settle the tax within the stipulated deadlines, generally six months from the date of death, with the possibility of an extension for the same period if requested within the first five months.
It is important to highlight that tax liability may extend to those who receive non-inventoried assets, which poses an additional challenge in managing inheritance inventories. In our practice, we recommend ensuring a thorough identification and valuation of assets to mitigate tax risks.
The jurisprudence of the Supreme Court, such as the Judgment of March 15, 2025, has clarified that the heir's liability is limited to the specifically inventoried assets at the time of acceptance, but may extend if additional assets are discovered later.
The Tax Base and Its Reductions
The determination of the tax base in the ISD is based on the net value of the acquired assets and rights, deducting charges and deductible debts. This calculation, although seemingly straightforward, can become complicated due to valuations of real estate and complex rights, such as corporate shares.
At the state level, Article 20 of Law 29/1987 establishes reductions based on the degree of kinship, disability, and acquisition of the primary residence. These reductions, while beneficial, must be carefully applied to avoid errors in the declaration. Additionally, autonomous communities may establish their own additional reductions, which increases the complexity of the calculation.
For example, in Catalonia, specific reductions are provided for the acquisition of family businesses, which requires a detailed analysis to ensure compliance with specific requirements. In our practice, we have observed that a lack of attention to these regional particularities can result in incorrect settlements and costly litigation.
Regional Bonuses and Their Impact
Regional bonuses in the ISD are a crucial element that can significantly influence the tax burden of an inheritance. These bonuses, which can vary widely among communities, must be carefully evaluated in the context of succession planning.
For instance, in the Community of Madrid, there is a 99% bonus for transfers between parents and children, which practically eliminates the tax burden in these cases. However, in other communities like Andalusia, the bonuses are less generous, which can lead to significant inequalities in the tax treatment of similar inheritances.
Given this landscape, it is crucial for professionals in inheritance law to conduct a comparative analysis of the applicable bonuses, considering not only the current regulations but also potential reforms in progress that could alter the tax landscape in the short term.
Practical and Controversial Aspects
In our daily practice, one of the most common challenges is the accurate valuation of assets, especially when it comes to real estate or complex financial assets. Discrepancies in valuations can lead to significant adjustments in the tax base and, consequently, in the tax amount.
Another area of frequent litigation is the application of regional reductions and bonuses. The diversity of regulations generates confusion and common errors in self-assessment, which can result in penalties and surcharges. The recent doctrine of the TEAC from 2026 emphasizes the need for adequate documentation and justification of the reductions applied.
- Conduct a thorough evaluation of all assets before the declaration.
- Consider applicable regional reductions and bonuses.
- Document all valuations and tax justifications in detail.
In conclusion, the proper handling of the Inheritance and Gift Tax requires a meticulous and well-informed approach. Tools like LexPartis enable professionals to manage these processes with greater rigor and efficiency, ensuring that all regulatory and procedural aspects are duly considered and executed.