Spanish lawyer and tax adviser · Valencia Bar (ICAV) no. 15042
Got a letter from the Spanish tax office about your property's value?
Hacienda, the Spanish tax authority, wants more transfer tax, inheritance tax or gift tax because it has used the Catastro's reference value, or because it doesn't accept the value you declared. I'm a Spanish tax lawyer, I work in English, and I'll tell you whether the letter can be challenged.
What this letter is
Most of these letters are a propuesta de liquidación: a proposed tax assessment. Hacienda tells you how much more it intends to charge and gives you a short window to reply with your arguments, which are called alegaciones. If you don't reply, or your reply is rejected, the proposal becomes a liquidación, a final assessment you have to pay or appeal.
They usually come after a purchase, an inheritance, a gift, or the division of a property owned with someone else (extinción de condominio, for example when a couple who bought together split up and one keeps the house). I'm based in Valencia and work with owners all over Spain, including the Costa Blanca and the rest of the Comunitat Valenciana.
The clock is running
Before I look at the figures, I look at the date the letter reached you, because it decides what can still be done.
- If you have a propuesta de liquidación, you can reply within the deadline stated in the letter itself, normally between 10 and 15 days.
- If you already have a final liquidación, you have one month to file an appeal with the tax office (recurso de reposición) or a claim before the TEAR, the regional tax tribunal that reviews the tax office's decisions.
- If no letter has arrived but you already paid tax on a reference value you think was too high, you can ask for the return you filed to be corrected (rectificación de autoliquidación) within four years and get back what you overpaid.
Missing the first deadline doesn't close every door, because the appeal and the tribunal are still there, but you are then arguing against an assessment that has already been issued.
What's at stake is the extra tax and, in some cases, a penalty. A penalty is not automatic: there has to be unpaid tax and fault on your part, and for a minor infringement it is 50% of the unpaid amount. If you reply in time and Hacienda accepts your arguments, there is no assessment, and without an assessment there is nothing to penalise. If there is one, the penalty goes through a separate procedure in which Hacienda has to prove fault. Nobody can guarantee the outcome: at least one tax tribunal has upheld a penalty for declaring below the reference value.
Why Spain says your property is worth more than you paid
The Catastro is the Spanish land registry for tax purposes, and the valor de referencia (reference value) is a figure it includes in each property's cadastral description, with a 0.90 reduction factor built in. The Catastro has never been inside your house: it values it from statistics for the area. Sometimes it gets it right, and sometimes it gives a swimming pool to an empty plot.
Since a 2021 reform (Law 11/2021), Spanish law uses that figure as the tax base.
For property transfer tax (ITP), the tax base is the reference value unless the value you declared or the price you paid is higher, in which case the higher figure is used. If dividing a jointly owned property was taxed as stamp duty (AJD), the base is calculated the same way. If a property has no reference value, or it can't be certified, the base is the highest of the declared value, the price and the market value.
For Spanish inheritance and gift tax, the law follows a parallel rule: properties are valued at their reference value.
The law presumes the reference value is correct "unless proven otherwise". In February 2026 Spain's Constitutional Court upheld the system in a transfer tax case (STC 13/2026). It also confirmed that the presumption can be rebutted with an expert valuation, and that the burden of proof is on the taxpayer. That ruling was about transfer tax; for inheritance and gift tax the rule in the statute is parallel, but the Constitutional Court hasn't ruled on it.
The Supreme Court has agreed to decide whether the reference value is the tax base "in all cases" or a presumption that can also be rebutted in court. That case was admitted in April 2026 and is still pending.
Reference value vs. a real valuation check
When your tax base is the reference value, Hacienda isn't technically checking your value: it is applying one. Spanish law says there is no valuation check in that case, and no right to the independent counter-valuation procedure (tasación pericial contradictoria). You challenge the reference value by appealing the assessment or asking for your return to be corrected, with an expert report showing the property is worth less. That is what a valor de referencia appeal really is. At the correction and appeal stages, Hacienda must ask the Catastro for a report, and that report is binding on it. Before the regional tribunal, the report is also mandatory.
When a property has no reference value and Hacienda carries out a traditional valuation check (comprobación de valores), different rules apply. Hacienda must justify an individual value for your property, and multiplying by a standard coefficient is not enough. Its surveyor must visit the inside of the property unless there is a stated reason not to. And you can ask for the counter-valuation procedure.
How I challenge it
I check the file, and whether Hacienda had grounds to open it
I read the whole letter: which value was applied, where it comes from, what procedure was opened and whether every deadline was met. Spain's Supreme Court ruled in 2025 that the tax authorities must explain why they are checking a return, and that if they don't, the assessment is annulled (STS 1482/2025). Sometimes the weak point is the procedure itself and the value never needs to be argued.
I prove the real condition of the property
The reference value doesn't know your roof has fallen in. If the property is in ruins, uninhabitable, under a demolition order or in need of works that change everything, I document it with photos, technical reports, town hall files and builders' quotes. In 2025 a regional high court in Castilla y León applied the ruin coefficient to a "manifestly uninhabitable" building and, because the recalculated value fell below the price paid, used the price as the tax base. In a traditional valuation check, I also look at whether Hacienda's surveyor actually went inside.
I commission an independent valuation
Because the burden of proof is on you, when the case calls for it I commission an expert report from an independent surveyor. In December 2025 the High Court of the Comunitat Valenciana held that a taxpayer's expert report had rebutted the reference value (STSJCV 903/2025). The same court did not simply accept the value the taxpayer had declared. The value you end up with is the one the expert can prove, which may not be the figure in your deed.
I file the alegaciones
The reply to the proposed assessment carries all of the above. Under the law, the reference value is formally challenged on appeal or in a correction request, but the alegaciones are the first chance to show Hacienda what it doesn't know about the property, and sometimes that is enough to close the file.
Appeal, tribunal and, if needed, court
If Hacienda issues the assessment, I appeal within one month, with the Catastro's binding report in the process, or take it to the regional tribunal, also within one month, where the expert evidence can be requested. After that, the next step is the regional High Court. Before each step I tell you what I think the chances are and what it will cost, and you decide whether to go on.
A real case
A property on the coast of the Comunitat Valenciana had a reference value more than four times its purchase price. The building was in ruins. At the alegaciones stage I filed the evidence of its real condition, and Hacienda closed the procedure without issuing any assessment. No appeal was needed. That result says nothing about yours, but it shows what proving the facts early can do.
Fees
I work with two formulas.
In the first, you pay a fixed fee plus a percentage of the tax you save compared with the proposed assessment, or of what you get back if you had already paid.
In the second, you pay nothing upfront and I charge a higher percentage only if we win. I offer this one only when, having seen the file, I think the case is clearly viable, because I'm the one taking the risk.
You get the price in writing at our first contact, before any work starts. If your case needs an expert valuation report, I include its cost in that same quote, so there are no surprises. Neither formula comes with a promise of the outcome: I tell you what I see in your case, including what works against you.
A Spanish lawyer who works in English
I'm Alberto Valiño Arcos, a lawyer and tax adviser registered with the Valencia Bar (ICAV) under no. 15042, with my practice in Valencia and more than twenty years of experience. My field is the taxation of inheritances and of property owned jointly, and I've studied thousands of property divisions between co-owners. I wrote Paga menos por tu herencia (Sepín), I'm finishing a book on dividing jointly owned property, and I contribute to Lefebvre publications. I handle each file myself and sign every filing.
The proceedings with Hacienda are in Spanish. I write and file everything in Spanish, and I explain each letter, each step and each decision to you in English, in writing and on the phone.
Send me the letter
Attach the letter as you received it and tell me when it arrived, because that sets the deadline. I'll reply with what I see, how much time you have and a written price.
FAQ
Can the Catastro's reference value be appealed?
Yes. Spanish law presumes it is correct unless proven otherwise, and in 2026 the Constitutional Court confirmed, in a transfer tax case, that it can be rebutted with expert evidence. You challenge it by appealing the tax assessment or by asking for your tax return to be corrected, not on its own. The burden of proof is on you, so you need an expert report showing the property is worth less.
How long do I have to reply to the letter?
If it is a proposed assessment (propuesta de liquidación), the deadline is stated in the letter and is normally between 10 and 15 days. If it is already a final assessment (liquidación), you have one month to appeal to the tax office or to the regional tax tribunal. If you already paid and no letter has arrived, you have four years to ask for a correction and a refund.
Will I be fined?
Not necessarily. A penalty requires unpaid tax and fault, and for a minor infringement it is 50% of the unpaid amount. If you reply in time and Hacienda accepts your arguments, there is no assessment and nothing to penalise. If there is an assessment, the penalty goes through a separate procedure where Hacienda has to prove fault, and nobody can guarantee the result.
I already paid transfer tax on the reference value. Can I get the difference back?
You can ask for your return to be corrected within four years. You need expert evidence that the property was worth less, and Hacienda must ask the Catastro for a report, which is binding at that stage. If the request succeeds, Hacienda refunds what you overpaid.
Does it matter that the property was in ruins or needed renovation?
Yes, if it can be proved. The reference value doesn't reflect the condition of each property, and its real condition is one of the most useful pieces of evidence against it. A Spanish regional high court applied the ruin coefficient to a manifestly uninhabitable building in 2025. A home that only needs renovation gives less room than one in ruins, and what counts is what the expert can document.
Do I need to be in Spain?
No. You send me the letter, we talk by phone or video call, and I deal with Hacienda for you. If I need your signature on an authorisation to act on your behalf, I'll tell you which document it is and how to sign it from where you live.
Will everything be in Spanish?
The proceedings will. The procedure is conducted in Spanish, so I draft and file everything in Spanish. You get every letter, step and decision explained in English, so you always know what is being said on your behalf and why.