Taxes, along with fees and Special assessment tax, conform the ensemble of tax revenue, which is the main source of funds of the Public Administrations Budgets. The importance of each of these revenue sources can differ depending on the branch within the Public Administration. According to the tax collection data of 2015 fiscal year, the tax revenue attributable to the State represented 84% of the total amount of its non-financial revenue. On the other hand, fees are an important resource for those bodies providing public services. Special assessment taxes only exist in local Administrations.
In the Ministry of Finance and Civil Service, all elements related to the tax system are carried out through the State Secretariat for Finance:
- State Tax Administration Agency: Effective application of the state tax and customs system (management, inspection and tax collection).
- Directorate-General for Taxation: Analysis and design of the global policy on the state tax system; proposal, preparation and interpretation of national tax regulations; negotiation and application of double taxation conventions, as well as other actions within the international tax field.
- Directorate-General for Cadastre: The Property Cadastre is an administrative registry which contains physical, economic and legal details of properties. The Directorate-General for Cadastre is in charge of creating and maintaining the Cadastre, which includes, among other tasks, the assignation of a cadastral value to each property, for the purpose of establishing the economic capacity arising from the ownership of such properties. This administrative value is used in several tax processes, namely in the Property Tax and the Tax on the Increase in the Value of Urban Land. In addition, the information contained in the Cadastre facilitates the performance of tax control duties by state, autonomic and local Administration authorities.
- Economic-Administrative Courts: Resolution of economic-administrative claims.
- Institute for Fiscal Studies: Investigation and study of issues related to public revenue and expenditure, as well as the analysis and elaboration on tax statistics.
- Taxpayer Protection Council: Its goal is to enhance the protection of the rights and guarantees inherent to citizens with regard to tax matters. It is also in charge of informing about any complaints and suggestions lodged in this regard.
- The General Secretariat of Regional and Local Funding, has commissioned the study, report and proposal of rules and measures relating to the tax regime of territorial entities and to special tax regimes by reason of the territory, without prejudice to the powers of the General Directorate of Taxes, the application of the concert regimes with the Basque Country and agreement with the Regional Community of Navarre as well as other functions related to the application and management of autonomous and local financing systems.