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How to check the authenticity and integrity of an official document with the CSV, CEA or CVE codes

27 mayo, 2021

Almost all of the documents that we receive electronically from the administration, also many of those that are physically delivered to us, have a verification code that allows us to verify that the file is authentic. It is, to understand us, like the ink stamp of yesteryear.

Normally we will find in these documents three types of codes made up of numbers and letters: the secure verification code or CSV, the electronic code of authenticity or CEA and the electronic verification code or CVE. For the issue at hand, which is knowing how to check if a document is official, all three are practically the same.


These codes are used both to know if a document is authentic and to verify its integrity, that is, that it has not been tampered with.

This check can be useful to know that we are in front of a truly official document or, also, to verify its integrity. That is, knowing that the document in our hands has not been tampered with and corresponds exactly to the one issued by the administration on duty.

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How to verify that an official document is legitimate and has not been tampered with

Text indicating the secure verification code and the method to verify the document in which it appears.

Text indicating the secure verification code and the method to verify the document in which it appears.

These security codes, created by a mathematical algorithm that unequivocally associates a document with its original, They are verifiable through the web pages of the administrations responsible for the documents in which they consist. Normally, next to these alphanumeric keys, the way in which we can verify said authenticity appears.

For example, this is how we can see it in our income tax return. In the PDFs that are generated when we file our personal income tax return, at the end of them, we find a text similar to the following:

The authenticity of this document can be verified using the Secure Verification Code [código alfanumérico] at https://www.agenciatributaria.gob.es

Page of the verification procedure for the secure verification code of a Tax Agency document.

Page of the verification procedure for the secure verification code of a Tax Agency document.

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In this case, we should access the indicated address and look for the procedure in question, called Document collation using secure verification code (CSV) by the Tax Agency. Accessing it, we must choose the option that we prefer from those offered to us and simply copy the code in question that appears in our document.

After that, the document in question will be offered to us in its entirety if the code is correct. If this happens, we can be sure that it is official.

These codes should be treated with caution and should not be passed on to third parties; with them, a third person could access the original documents and even carry out procedures on our behalf

The second step, if the document has come to us through a third party such as a consultancy, for example, is to compare the document we have and the one issued by the administration to ensure that our copy has not been tampered with.

With the rest of administrations, the steps to follow are the same. If there is a website together with the verification code, we access it; if not, we look for the name of the code next to the name of the responsible administration in any search engine or we dive into the portal of said administration and locate the procedure, ensuring at all times that we are in front of the legitimate website, of course.

Finally, it is important to note that these codes should be treated with caution and should not be passed on to third parties. Anyone who obtained the code present in our income tax return, for example, could access it only by following the steps described. Even if the code is that of a notification, if necessary, it could carry out processing on our behalf, so it is important to keep the CSV, CEA and CVE safe.