Cadastral reference value: what it is, where to check it and how to appeal against it

What it is used for

In Spanish tax practice, the reference value acts as the minimum tax base in key scenarios:

• ITP (Property Transfer Tax on resale properties) and, within the ITP-AJD tax framework, the base for AJD (Stamp Duty) where applicable.
• Inheritance and Gift Tax (ISD) in transactions involving real estate.
• Wealth Tax in the valuation of real estate assets according to the applicable regulations.

The usual rule for transfers for consideration is set out in Article 10 of the recast text of the Law on Property Transfer Tax and Stamp Duty (TRLITPAJD): the tax base is whichever is the higher figure between the agreed/declared price and the cadastral reference value. If you buy below this reference value, the tax authority may calculate the tax due based on the reference value, rather than the amount stated in your contract.

Constitutionality: STC 13/2026

The use of the reference value generated legal debate. The Constitutional Court, in its ruling STC 13/2026 of 12 February (published in the BOE on 19 February 2026), declared the system constitutional within the terms challenged in those proceedings. While this does not remove standard administrative procedures for disputing a specific property's value, it confirms that the legal framework introduced by Ley 11/2021 was not invalidated in its entirety by that judgment.

Where to check it

Official enquiries are made via the Cadastral online portal (sede electrónica del Catastro) and the services provided by the General Directorate for Cadastre to check the reference value associated with a specific cadastral reference number. You need to identify the property accurately (cadastral reference, address, or ownership details for authorised checks).

If you are buying, ask the seller for the cadastral reference or extract it from the land registry extract (nota simple) and check the reference value before calculating taxes and your required deposit. If you are selling, it is advisable that the buyer knows this figure to align their financing plans.

Reference value, cadastral value and market price

Three distinct concepts:

• Cadastral value: the standard base for IBI; it is revised in general assessment cycles and subject to local tax relief.
• Reference value: the benchmark figure used as the tax minimum in property transfers and the other taxes mentioned.
• Market value: what a real buyer pays under normal supply and demand conditions.

These values can diverge significantly in high-demand areas or for properties with unique characteristics. A professional market valuation helps establish the asking price; the reference value defines the minimum tax floor.

What to do if you disagree

Disputing the reference value is not the same as negotiating the sale price. The standard legal options (depending on the stage of proceedings) include:

1. An appeal or administrative complaint through the appropriate channel against the tax assessment or valuation audit.
2. An expert counter-valuation (tasación pericial contradictoria) where permitted by law to establish a value different from the reference figure, subject to formal requirements and deadlines.
3. Seeking tax advice to weigh up the cost-benefit ratio of appealing versus paying the assessment and moving forward.

Deadlines are strict. If you receive a proposed tax assessment or valuation audit notice, do not miss the administrative deadlines.

In buying and selling property

For the buyer, a high reference value increases ITP/AJD tax liability and may require a larger cash deposit. For the seller, the reference value does not replace the negotiated price, but it does define the tax threshold that the authorities can demand from the buyer (which, in practice, affects the viability of the sale).

Before listing a property, an indicative valuation aligns price expectations with market reality and tax implications. At Sky Real Estate, you can request an informative property valuation via property valuation.

Inheritances and gifts

In gratuitous acquisitions (inheritances and gifts), the reference value can also set the tax minimum. Autonomous Inheritance and Gift Tax (ISD) rates and exemptions vary by region. Verify the regional regulations and the property's reference value before agreeing to estate distribution or property partition.

Common mistakes

• Confusing the cadastral value used for IBI with the cadastral reference value.
• Signing a preliminary deposit agreement (arras) without calculating taxes against the current reference value.
• Assuming that stating a lower price in the title deed protects the transaction from tax scrutiny.
• Ignoring a supplementary tax demand arising from a valuation check.

Related articles

If you are selling, check our articles on municipal capital gains tax (plusvalía municipal) and personal income tax (IRPF on property sales). If you are buying, your mortgage assessment should account for taxes calculated on the correct statutory base.

To market a property with realistic pricing and tax clarity, our property sales and marketing service begins with a realistic valuation of the asset.