The most common forms of legal entity under Spanish corporate law are the corporation (Sociedad Annima - S.A.), and the limited liability company (Sociedad Limitada -S.L.) (other corporate forms are described in Appendix I, section 2 of this Guide).

Madrid is the autonomous community with the highest income per capita in Spain, at 38,435 in 2024  significantly above the national average and ahead of the Basque Country, with 35,832, Navarra, 33,798, and Catalonia, 32,550. In that year, the GDP per capita growth was 8.6%.