Against a background of economic development in the 1960s, Banco de Bilbao grew further, absorbing other banks. At the same time Banco de Vizcaya also continued to develop as a modern universal bank and began to emerge as an important financial group. Greater flexibility by the authorities with regard to new branches allowed it to extend its network. 

Caja Postal added current accounts, securities and specific credit lines to its existing services.

The Banking Sector Reform Act 1962 nationalised BCI, BHE and BCL and converted the Servicio Nacional de Crédito Agrícola into Banco de Crédito Agrícola (BCA). All four thus became public entities. However in 1971 they were recast as joint stock companies and became official loan entities (under the Official Credit System Act). 

During the 1980s Banco de Bilbao’s strategy was to attain sufficient size in order to participate in financial operations generated by advances in technology, deregulation, securitisation and the interrelationship between domestic and international markets.

Banco de Vizcaya contributed to the refloating of banks affected by the economic crisis and pursued a policy of strong growth through acquisitions. This turned it into a large banking group. The most important operation was the acquisition of Banca Catalana in 1984.

In the meantime the official credit entities expanded their business through market operations. In 1982 BEX lost the exclusive right to provide export finance. It refocused its goals on becoming a universal bank and on building a financial group. During this process it acquired Banco de Alicante in 1983.

In 1988 Banco de Bilbao and Banco de Vizcaya merged to form BBV. 

Corporación Bancaria de España (CBE) was set up in 1991 as a government corporation and credit entity with bank status. Argentaria started out with a federated banking model. However in 1998 Corporación Bancaria de España (already privatised via IPOs), BEX (which had merged with BCI), BHE and Caja Postal were merged into a single bank: Argentaria.