In addition to tax relations, the Economic Agreement sets up the general principles applicable to the financial and budgetary flows between the Basque Country and the Spanish state, stipulating each of them and determining the methodology for their quantification.

Together with the constitutional principle of solidarity, the most outstanding principles concerning financial relations are:

• Fiscal and financial autonomy of the Basque Country.
• Coordination and cooperation with the State in matters of budgetary stability
• Contribution by the Basque Country to the State’s expenses concerning non-assummed competences, by means of the payment of the Quota.

Within the scope of local entities, the Economic Agreement confers to the competent Institutions of the Basque Country the same faculties of financial supervision as the ones executed by the Spanish state at any time, without this being construed to mean that Basque Municipalities shall have a lower level of autonomy than the one enjoyed by the ones under the Common Regime.