Through the Undersecretariat of the Interior and its superior body, the Directorate-General for Internal Policy, the Ministry is responsible for all actions related to ensuring political pluralism and the proper functioning of electoral processes.

The Minister is assisted by three main officials, the Secretary of State for Security, the Secretary-General for Penitentiary Institutions and the Under-Secretary of the Interior.

As of 2022, central, regional and local governments in Spain spend around €26 billion per year (1.9 % of GDP) on security and public order.

In 1832 the Ministry of Development was created, which assumed security competences, fleeing from the denominations of "Interior" and "Governance" since they were reminiscent of the time of the war against Napoleon.

[citation needed] In 1847, all matters related to the services of public, economic and cultural works were disbanded from the Ministry of the Interior.

The Ministry of the Interior maintained the functions of public order, municipal and provincial organization —being responsible for the Civil Governors—, health, post and telegraph, and the Overseas Office was incorporated.