[4] Galp consists of more than 100 companies engaged in every aspect of the oil and natural gas supply, hydrocarbon exploration and production; refining, trading, logistics and retailing; co-generation and renewable energy.

[5] Galp can trace its origins back to 1848 and the installation of Lisbon's first gas street lamps, but the current incarnation was formed through the merger of Petrogal, Gás de Portugal and Transgás, on April 22, 1999.

After the Carnation Revolution 25 in April 1974, Portugal gave independence to its overseas provinces, with the ownership of the local SACOR branches being ceded to the new countries.

In April 1976, Petróleos de Portugal (PETROGAL) was formed by the merger of SACOR with three other nationalized oil companies (CIDLA, SONAP and PETROSUL).

In 1999, Galp Energia is created as the holding company for the Portuguese State-owned oil and gas business, controlling PETROGAL and Gás de Portugal (GDP).

[12][13] In 2016, Galp and Petrobras broadened an existing cooperation accord to include offshore oil research and development projects and exploration and production partnerships.