Encarna Robles is a secondary school teacher in Murcia and since 2022 has let a flat in Cartagena to a family on a long-term contract. From the start she has had her income tax return done by a neighbourhood gestoría, a local firm that handles tax and paperwork. In April 2024 she emailed them the contract and a summary of the rent received in 2023. The 2023 return was filed without the rental. In September 2026 she receives a proposed assessment: 2,800 € of tax, some late-payment interest, and a warning that penalty proceedings will be opened. The gestoría replies that the email "never reached them". Encarna has the sent email, with the attachment, in her mailbox.
Her question has two answers, because there are really two separate legal relationships: hers with the Agencia Tributaria, the Spanish tax agency, and hers with the gestoría.
As far as the tax agency is concerned, you are the one liable
The tax agency only knows Encarna. She is the taxpayer for income tax (IRPF), and having delegated the filing does not pass the debt on to anyone. The tax is owed because the rental existed and was not declared; the late-payment interest, because the money was in her account instead of in the Treasury. Neither depends on who was at fault, and article 26.1 of the General Tax Act (the Ley General Tributaria) says so expressly for interest: it does not require "culpable delay".
The penalty is another story. It is the only one of the items that requires fault, and that is where the gestoría's mistake really carries weight.
Where the professional's mistake comes in: fault
Article 179.2.d) of the Act excludes liability for an infringement where "the necessary diligence" has been shown in meeting one's obligations. A taxpayer who entrusts her return to a professional, hands over complete documentation on time and has no tax training is in a reasonable position to argue that she, at least, was diligent.
The April 2024 email is the key piece of evidence. With it, Encarna can argue in the penalty proceedings that the omission was not due to carelessness on her part but to a failure in the chain of instructions. It is not an automatic defence: the tax agency may reply that checking the draft before signing was also part of the diligence required, and the courts have not always decided the same way. But it is a well-founded argument, and the Administration has to explain why, despite it, it finds negligence.
While the penalty is being contested, the assessment of the tax follows its own course. If Encarna lets the payment deadline pass while waiting to see what the gestoría says, the debt enters the enforcement period with its surcharge, and that surcharge will be hard to pass on to anyone: it will have been caused by her own delay.
Encarna's account, item by item
Let us assume late-payment interest of 310 € and a penalty of 50 % of the tax, which is the minimum for infringements with a base below 3,000 € under article 191.2. Let us also assume that, to defend herself and make the claim, she pays 600 € in fees to another professional.
| Item | Amount | Can it be disputed with the tax office? | Is it loss that can be claimed from the gestoría? |
|---|---|---|---|
| Tax | 2,800 € | Only if the calculation is wrong | Normally not: it was her own debt |
| Late-payment interest | 310 € | No | Arguable |
| Penalty | 1,400 € | Yes, for lack of fault | Yes, if it ends up being paid |
| Defence fees | 600 € | No | Yes, if they result from the mistake |
The right-hand column is the one that surprises people most. The tax is not a loss caused by the gestoría, because Encarna would have paid it anyway if the return had been filed correctly. The interest is more debatable: it compensates for money she had available during that time, and some argue that for that reason it is not a loss either. The penalty and the fees are, because they would not exist without the mistake.
If the lack-of-fault argument succeeds, the penalty disappears and what can be claimed from the gestoría shrinks to the fees, and perhaps the interest. If it fails and Encarna pays the penalty, the amount that can be claimed rises. That is why it makes sense to take the two things in that order: first the penalty is fought, and then whatever is left is claimed.
What has to be proved against the gestoría
The claim is a civil one. Article 1101 of the Civil Code requires anyone who, in performing their obligations, is guilty of wilful misconduct, negligence or delay to pay compensation. Three things have to be shown:
- The engagement and its scope. A signed engagement letter is ideal. If there is none, invoices from previous years and the emails in which the return is requested will do.
- The breach. That a diligent professional would have included the rental with the documentation received. This is where the April 2024 email does all the work.
- The loss and its link to the breach. The items in the table, with proof of payment.
If the gestoría has professional liability insurance, article 76 of the Insurance Contract Act allows a claim to be brought directly against the insurer. It is worth asking in writing whether the policy exists and with which company, because many claims are settled at that stage without reaching court.
As for the time limit, article 1964.2 of the Civil Code sets five years for personal actions without a special period, counted from when performance can be demanded. When that period starts to run for a tax mistake, whether from the filing of the return or from when the loss becomes known, is open to argument. It is better not to leave it to the last minute.
If you are in a similar situation, you can send us the proposed assessment and your correspondence with your adviser through the voluntary correction form, and we will separate what is disputed with the tax agency from what is claimed from the professional.
The order that avoids losing ground along the way
- First, the tax agency's deadlines. The proposed assessment opens a period for submissions, and the penalty proceedings will open another. They are answered on time, even if the conversation with the gestoría is still going on.
- Next, the documents. Ask the gestoría, in writing, for a copy of the file for the 2023 return and of the communications received. If they claim they did not receive the email, it helps to have the proof of sending and, if possible, some later reply from them showing that the address worked.
- Finally, the claim. With the penalty already decided, the actual loss is quantified and claimed, first out of court.
There is a common mistake at this stage: writing to the gestoría, angry, before having the file. A defensive written reply from them can later complicate an agreement that would have been quick.
When the professional also filed in your name
In many cases the gestoría does not just prepare the return: it files it with its own certificate, as representative or as a "social collaborator" authorised to file for others. That does not change who the taxpayer is. Representation allows someone to act on another's behalf, but the debt and any infringement are still the taxpayer's. What does change is the evidence: if the gestoría filed, the online office holds a record of who did it and when, and that information is part of the file worth requesting.
When the mistake is spotted before anything arrives, the path is different: correct it as soon as possible, with a surcharge and no penalty, and then claim the surcharge. How that correction is made is in how a return already filed is corrected, and the difference between a surcharge and a penalty is in surcharge, interest and penalty.
We do not guarantee that the penalty will be cancelled or that the claim will succeed; with the documents in front of us, we tell you what chances each front has and what it costs to pursue. That work is part of Salama Tax's voluntary correction service.