Some high courts of justice are already raising doubts about the automatic application of the reference value, forcing “pay first and challenge later”. Besides, the Constitutional Court has recently admitted a question of unconstitutionality raised by the High Court of the Andalucian Community, which questions whether this mechanism violates the principles of economic capacity and reserve of law in tax matters.
There are many issues discussed in the courts in relation to the procedure for verifying the value of real estate. Among others, there are numerous judgments in which the courts have annulled the settlements issued as a result of these verifications, when it has been shown that they are not correctly motivated. In this area, special attention has been paid to those cases in which the Administration has not carried out an eye visit of the property, which the Supreme Court has recalled in its recent judgment of 24 June 2025 (appeal 6908/2023).
In this resolution, the court annuls a judgment of the National Court that had considered valid an expert appraisal based exclusively on an exterior inspection with photographs. Reaffirming a long line of jurisprudence, the Supreme Court recalls that the interior inspection is not a superfluous formality, but an essential guarantee to correctly single out the value of the property, especially when aspects that are not appreciable from the outside and with an impact on the individualized valuation of the property are discussed. The judgment insists that the absence of an interior visit can only be accepted if it is duly justified by the expert, on a case-by-case basis, providing specific documentation explaining why it has not been possible or has been considered unnecessary.
This requirement is not new, but its reiteration acquires special relevance at a time when a new tax model based on standardized valuations is being consolidated. Thus, in the face of this doctrine (now reinforced by the Supreme Court), the legislator reacted in the opposite direction by introducing the reference value, through Law 11/2021, of 9 July, on measures to prevent and combat tax fraud. This law amended Article 10 of the Consolidated Text of the ITPyAJD Law and Article 9 of the ISD Law, so that, since said reform, the taxable base in real estate transfers is presumed to coincide, at least, with the reference value determined by the General Directorate of the Cadastre, unless proven otherwise by the taxpayer. This value is defined in the Cadastre Law as an objective value with exclusively tax effects, calculated from the prices of sales formalized before a notary and subject to the application of a reduction coefficient, without there being public information on the way in which the aforementioned value is determined.
Since the introduction of the reference value, the regulations require the taxpayer to always settle, at least, for that value and, only afterwards, challenge the assessment if he considers that the amount paid is inadmissible. It is sufficient that there is a reference value, without the need for further individualized administrative justification or application of the methods of Article 57 of the General Tax Law (LGT), for this value to be the basis of the tax to be paid, given that the new system presumes its correction without verifying the specific circumstances of the asset or the real context of the operation.
This approach creates particularly problematic situations in the case, for example, of properties acquired at public auction, subsidized housing or transactions subject to an assessed administrative price, in which the purchase price cannot exceed an amount set by law or by a court of law. Despite this, the Directorate General of Taxation has confirmed (among others, in its resolution V0435-25) that the acquisition of a protected home (subject to the maximum legal price) must be taxed at the reference value, even if this is higher than the appraised price, obliging the taxpayer to settle according to said value and, where appropriate, to subsequently challenge the settlement paid if you do not agree. This criterion has been ratified by the Central Economic Administrative Court in resolution of 17 November 2023 (8609/2023).
However, the issue is still alive in the courts.
In its recent judgment of 10 July 2024 (appeal 160/2023), the High Court of Justice of the Valencian Community considered that the automatic application of the reference value within a limited verification procedure is equivalent, in practice, to a true verification of values using the method of coefficients on the cadastral value (art. 57.1.b LGT). Consequently, it declared that the taxpayer could request and obtain the suspension of the debt while the contradictory expert appraisal is being processed, since the Administration, despite being protected by the legal presumption, has de facto carried out an assessment that must be subject to the guarantees provided for in the LGT. This judgment reinforces the idea that the reference value cannot be erected as an insurmountable barrier and underlines the validity of the taxpayer’s rights of defence, even in the new regulatory landscape.
For its part, the Supreme Court has been recalling, although still in relation to the previous regulations, that the burden of proving the inaccuracy of the declared value cannot automatically fall on the taxpayer, warning, albeit subtly for the time being, of the risk of consolidating a quasi-automatic tax valuation system that ignores the uniqueness of the asset (see judgments 1391/2022, 75/2023, 1915/2024 or 1942/2024). That warning could show a certain willingness on the part of the Supreme Court to examine this valuation regime in greater depth when it is presented in terms of legality in the context of a possible appeal in cassation.
In short, the reference value system raises, and this is what the courts are appreciating, serious legal and practical doubts. Designed for anti-fraud purposes, its indiscriminate application (even in appraised transactions or those with a public or intervened price) and its requirement to “pay taxes first and discuss later”, make it an instrument of presumed taxation without real guarantees of contrast and that possible suffers from defects of unconstitutionality.
Along these lines, on 8 July 2025, the Constitutional Court has admitted the question of unconstitutionality raised by the High Court of Justice of Andalusia on 5 May 2025, in which this court stated that the automatic application of the reference value (in the manner set out above) could violate the principles of economic capacity and reserve of law in tax matters provided for in articles 31.1, 31.3 and 133.1 of the Spanish Constitution, by obliging to pay tax on a presumed value rather than on the real one.
The resolution could have a significant impact, both for the validity and interpretation of the current tax valuation model, and for the position of the Treasury in future challenges.
