The cadastre (@Haciendagob) it’s a administrative record, a large database containing all properties in the country, regardless of its urban or rustic nature, and where its main characteristics are reflected, including the surface, ownership or use to which they are intended.
This is a record compulsory and free, very important when establishing the amount of the Real Estate Tax (IBI), the amount of which takes the cadastral value as a reference.

What are the most frequent errors in the cadastre?
In general, the data contained in this registry is usually quite exact, especially with the arrival of new technologies, because in most cases it is not the citizen who must be in charge of sending the information regarding their properties to the cadastre.
The notaries and property registrars, are normally those who carry out the communication following any change that affects a property, as it can happen, for example, in a purchase-sale, a donation or in the segregation of a plot. Also their own town halls or the Tax Agency They provide those data that they consider should be incorporated into the cadastre, so that they are taken into account in future taxes.
Sometimes it is the individual who can initiate the process. Imagine that you have a single-family house and you have expanded the constructed area or your community of neighbors has decided to build a swimming pool in the communal garden area, these are cases in which it is It is mandatory to present the modifications made in this registry, because sooner or later the change will be detected.
Despite the fact that the cadastre stays updated On a constant basis, errors may occur that are detrimental to the taxpayer and are always of interest to correct. Among those that occur most frequently you can find:
- The cadastral reference does not match the property. It can happen, for example, when faced with new constructions, your home changes its numbering.
- The boundaries real values between parcels do not coincide with those that appear in the registry, altering the cadastral value of a property.
- You still appear as headline of a property because, for whatever reason, your deregistration did not occur.
- The surface of your home appears increased in meters after a review, because they have considered a constructed area something that is not. For example, you have a shed to store tools or garden equipment and the visual inspection has considered it to be a home.

What can be done in these cases?
If you have any questions or think that there is an error in the cadastral information that affects you, the first thing you have to do is confirm it. Do you have three ways to request it and get it.
- Through the campus Cadastre electronics.
- In the different territorial offices (managements).
- In the Cadastral Information Points that you can find especially in town halls and also in other public bodies.
In addition to informing you, it is also convenient to ask for the corresponding cadastral certification that you will need to start any data change request process. It is important to differentiate between errors that can occur immediately after adding new data and those that persist over time.
If you receive a notification from the cadastre, in which it advises the resolution of an application or communication procedure (for example, the notary has communicated the purchase of the house you have just acquired) and you do not agree, you can file a Replenishment resource or a claim in the Cadastre Management to make the notification. You have a deadline of one month to do it.

Fix old mistakes, complicated but necessary
It is not easy because any modification of the cadastre it must be initiated by the trade registry itself. That is, as detailed by the Madrid City Council (@MADRID), it is the Administration that has to initiate what is called the discrepancy correction procedure. When there is a disagreement regarding the data reflected, which is also harming you in some way, what you can do is report the error as soon as possible.
Keep in mind that, in addition to requesting the correction in writing, you will have to provide documentation that supports it: public deed, certificate of the property registry, images on the ground that demonstrate your allegations or technical reports, among other data.
Once you have gathered all the information that can be useful to prove that the error exists, you should go to the management of the cadastre of your municipality in order to communicate the lack of concordance between what appears in the registry and reality.
In this way, in principle, the process would start, which has a resolution period of six months and that it will include a hearing with the interested party to try to clarify the matter. If you do not agree with the result, you can appeal administratively.
It is important to clarify that, logically, the claim can never refer to something that corresponded to communicate to the registry and has not been done. For example, if you have expanded the construction area, without declaring it, and you find that your IBI has increased, claiming does not make sense, since it is not an error but rather compliance with the obligation to communicate that change.
In any case, it must be remembered that through the Council for the Defense of the Taxpayer of the Ministry of Finance You can also present complaints and suggestions related to the cadastre.