Although the collection regulations establish different places for payment of debts collected by the state tax administration, these payments are made, in their entirety, through credit institutions authorized to act as collaborators.

For reasons of procedural economy, and to achieve the maximum possible agility in monitoring compliance with obligations by those obliged to pay, the collaborating entities centralize, at the national level, both the entry into the Treasury of the amounts collected by them such as sending to the Tax Agency the detailed information necessary for their management, imputation and monitoring.

The evident significance of what was mentioned in the framework of state tax revenues, the main financing item of the State budget, made it essential to create a Unit whose functions were specifically related to the provision of the collaboration service in state collection management by of credit institutions.

Thus, in 1995, the Presidency of the Tax Agency created the Control Unit of Collaborating Entities (currently, the Central Control Team of Collaborating Entities), which is integrated into the Collection Department, under the dependence of the General Subdirectorate of Coordination and Management.

Since its creation, this Unit exercises all the powers related to the actions of collaborating entities, which include the authorization of credit institutions to act as such, the control of their actions and the preparation of all those regulations related to the implementation of payments in favor of the state Public Treasury, both with regard to the design of new payment procedures and the use of new forms and means of making them.

Among the tasks carried out by the Collaborating Entities Control Unit, those aimed at ensuring that the detailed information provided by collaborating entities meets the quality standards necessary for the automatic imputation of income to the obligated parties should be highlighted, as well as those aimed at ensuring that, in each collection fortnight, the information provided by each of the collaborating entities coincides exactly with the amount they deposited into the Treasury account at the Bank of Spain.

This process of acceptance and balance of information from collaborating entities has a special relevance, since this process is a precondition for the accounting and application of income, which is why it constitutes an essential element for compliance by the Tax Agency with the tasks that are its own, with regard to the control and monitoring of tax obligations.

Finally, to the extent that this unit is in charge of regulating the incorporation of new ways and means of income, it can be said that it contributes directly to achieving the objective of making it easier for citizens and companies to comply with their tax obligations, which constitutes one of the fundamental purposes of the Tax Agency.