For each of the tax agreed figures, the Economic Agreement lays down the criteria by virtue of which the legislative, inspection and levying competences are distributed. In addition, the Economic Agreement sets the rules required to distribute the competences concerning specific, formal or material, issues in relation to each tax figure.
The Economic Agreement regime guarantees a comprehensive tax system, with the exception of the competences the Agreement confers exclusively on the State. In order to do so, the Second Additional Provision of the Agreement states that in the event of a reform of the State tax legal system affecting the taxes object of agreement, or an alteration in the distribution of the regulatory competences affecting the scope of indirect taxation, or new tax figures or payments on account, both Administrations shall by mutual agreement proceed to adapt the Economic Agreement to any modifications made in the aforementioned legal system. This provision guarantees that the agreed tax regime is anytime adapted to the actual situation and structure of the tax system in force in the State and justifies the harmonisation rule imposed on the Historical Territories at the time to establish their tax regime that obliges them to regard for the general taxation structure of the State.
Below you can find a chart of each of the agreed taxes, summarising the allocating factors for the legislation, inspection and levying capacities.