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Guide for the transfer of tax information electronically to Public Administrations for the exercise of their powers (PROTGEN)

1. Introduction

To accredit tax-related circumstances to other public administrations, the Tax Agency provides them with several ways of directly supplying information.

Pursuant to article 9 of the Order of 18 November 1999 New window regulating the provision of tax information to public administrations for the performance of their functions, as well as the cases contemplated in article 113.1 of the General Tax Law (95.1 current Law 58/2003-LGT) (BOE 30-November-1999), to the extent that public administrations may have access to the tax information they need for the performance of their functions through the channels provided for in this Order, interested parties will not be required to individually provide certifications issued by the State Tax Administration Agency (AEAT), nor to submit, in original, copy or certification, their tax returns. The supply of tax information regulated in this Order shall not have any effects other than those derived from the purpose for which they were supplied, or as a substitute, where appropriate, for the certification or declaration of the interested party.

However, as in many cases these are automated procedures, the tax information supplied directly to the competent Public Administrations in the administrative procedure in which it is included – which entails a denial or restriction of the rights of the taxpayer – must be communicated to the interested party before the administrative procedure is resolved to allow them to make allegations or correct any circumstance relating to the information on their tax situation, if appropriate.

The transfer of information to Public Administrations requires the consent of the citizen to whom the information refers.(1), unless provided for in a legal regulation.

The authorisation of the interested party shall state the administrative procedure and the authorised body, and shall not admit generic authorisations for any procedures or functions that may be carried out by the requesting body. The authorised body shall refrain from requesting data relating to the data subject if the data subject has withdrawn the initial authorisation given.

At present, there are several computerised ways of transmitting information:

  1. Immediate transfer of information in the Tax Agency's e-Office

  2. Obtaining tax certificates online at the AEAT Electronic Office.

  3. Web services.

    Each of these information transfer channels has its own particularities in an attempt to respond to the different technical situations of the entities receiving the information. Moreover, these procedures are constantly evolving in line with technological developments.

The Immediate transfer of information (CESII) is a web application used from the browser itself that allows, through the Electronic Office of the Tax Agency, the sending of an input file containing the request for information and the reception of an output file with the requested information almost simultaneously, which the user of the agency can download to his computer. These files relate to one type of information and can accumulate multiple contributors. No IT development is required on the part of the entity receiving the information and no software needs to be installed on the computer.

Obtaining tax certificates online is a procedure for requesting (by filling out an online form ) and obtaining (usually immediately) individualized third-party certificates (in PDF format with a secure verification code) through the Tax Agency's electronic office. It does not require any IT development on the part of the entity receiving the information.

Web Services technology allows for the online collection of information, in an automated manner. This system requires IT developments to be carried out by the entity receiving the information.

In addition, occasional requests for information other than that offered through the above channels will be processed through the Management of requests for unstructured information procedure, a formal mechanism for receiving requests and sending unstructured information to other organizations.


(1) On the Tax Agency website a model is provided where the interested party authorizes the public Administration to collect information from the Tax Agency New window . This form is not compulsory; each administration may use any other form adapted to the particular characteristics of the procedure in question. Thus, it is advisable that the application forms that the interested party must submit include a section containing the following text or similar : “The applicant authorizes the competent Body to collect tax data from the State Tax Administration Agency when necessary for the resolution of this procedure” .(Back)