[2] On the eve of Portuguese Angola's independence from Portugal following the Carnation Revolution and the election of a democratic government in Portugal in 1976, the company ANGOL (ANGOL Sociedade de Lubrificantes e Combustíveis SARL), founded in 1953 as a subsidiary of Portuguese company SACOR) was nationalized and split in two, forming Sonangol U.E.E.

Directive 52/76 instituted Sonangol as a state-owned company with a mandate to manage the country's substantial petroleum industry.

Using the extant remains of Texaco, Total, Shell and Mobil's oil works, Sonangol obtained the assistance of Algerian Sonatrach and of Italian Eni.

[5] In December 2013, Sonangol acquired the exploration rights to five onshore oil blocks in Angola, which could be tendered for development at a later date.

[6] According to the judgement of a Swiss court in 2020, Didier Kelley paid key Sonangol officials a total of US$ 6.8 million in bribes between 2005 and 2008 while CEO of SBM Offshore.

The terms of this contract stipulated that Sonangol would compensate Dream's Leisure for any net losses incurred through management of the hotel.

In the opinion of Rui Verde, a lawyer and legal expert of anti-corruption watchdog Maka Angola, "the contract clearly encourages Dream's Leisure to inflate costs and declare losses, in order to plunder the State as much as possible.

[12][13] This move was later described in 2020 as "tainted by illegality" by a Dutch international arbitration tribunal in Amsterdam, "to reap an extraordinary financial gain to the detriment of Sonangol and, consequently, of the State of Angola,"[14] which froze Exem's assets, ruling in favor of a legal complaint by Sonangol that Exem owes them the shares back because of the corrupt way in which they were acquired.

[19] In June 2016, President dos Santos removed the entire board of Sonangol, and installed his daughter Isabel as chairwoman of the company, to "ensure transparency and apply global corporate-governance standards".

One year later, Maka Angola reported that Isabel dos Santos demanded, with threat, that the Ministry of Finance inject three billion US$ into the company, claiming it was necessary to rescue Sonangol from immediate bankruptcy, though this was not granted.

[22] In November 15, 2017, the new President of Angola, João Manuel Gonçalves Lourenço, dismissed both Isabel and the entire board of directors under her and named Carlos Saturnino Guerra Sousa e Oliveira as the Sonangol chairman.

[31] In July 2019, President Lourenço canceled the Dream's Leisure contract, returning control of the Talatona hotel to the state.

[11] In April 2020, the Ministry of Finance began conducting a pruning of Sonangol's other functions, including a selling of its peripheral businesses such as its ventures in aviation, banking, hotels, and real estate, many of which were built during the regime of the dos Santos family.

[42] Sonamer is an oil and natural gas well drilling company established in 1998 between Sonangol (49%) and Pride International (51%), specializing in deep and ultra-deep waters.

[59] The facilities at the base include three quays for oil and gas ships to dock, with storage, catering, housing, and medical services on shore.

[62] OPS Servicos de Producao de Petroleos Ltd is a joint venture between Sonangol and SBM Offshore that operates and manages a fleet of five FPSOs owned by Sonasing: Kuito, Mondo, Sanha, and Saxi Batuque, as well as N’Goma, which was previously named Xikomba prior to a major refit.

[63] Sonangol Integrated Logistics Services operates a two-million square meter[64] petroleum industry onshore supply base in Luanda Bay with a 2 kilometer long quay,[65][66] equipment rentals, cargo facilities, warehouses, medical facilities, and other support services for ships.

[63] Empresa Nacional de Combustíveis, SARL (ENACOL) is owned by Sonangal (32.5%), Petrogal (32.5%), the government of Cape Verde (29.3%), and other minor partners.

[73] Empresa Nacional de Combustíveis e Óleos, SARL (ENCO) is the national fuel and gas company of São Tomé and Príncipe.

[74][75] Pumangol is a network of gas stations and airport and marine fuel terminals formerly belonging to Swiss oil company Puma Energy.

[87] In 1998, Sonangol incorporated a subsidiary in Kinshasa in the Democratic Republic of the Congo[88] as a 60-40 joint venture with Zimbabwean company COMIEX,[89] with the Congolese Minister of State, Pierre-Victor Mpoyo, as its first CEO.

[88] Sonangol Congo focuses on the importing, marketing, storage, transportation of refined oil products in the DRC.

[91] Established in 2002 as a joint venture between Sonangol (30%) and Technip Angola (70%), Angoflex is a manufacturer of submarine umbilicals and pipelines for the oil industry, with over 24 projects[92] completed for clients such as BP, Chevron, Eni, ExxonMobil, and Total.

[94] Porto Amboim Estaleiros Navais (PAENAL) was founded in 2008 as a joint venture between Sonangol and partner SBM Offshore, with Daewoo Shipbuilding & Marine Engineering joining in 2010.

It is equipped with a 490 meter quay and Jamba, the largest heavy lifting crane in Africa with a 2,500 ton capacity.

[96] Petromar builds, installs, and designs offshore facilities like oil platforms, cranes, and deep water equipment.

[97][98] Sonacergy Serviços e Construções Petrolíferas, Lda is a company that performs drilling, inspection, maintenance, assistance, and research of oil facilities.

[49][97][96] Sonamet Industrial S.A. manufactures oil platforms and other large metal structures from its production facilities in Lobito Bay.

[3] Sonangol held a 20% stake in the Société Ivoirienne de Raffinage oil refining company of Cote d'Ivoire until its sale of those shares in June 2024.

[106] Sociedade Distribuidora de Combustíveis, S.A. (Sopor)[116] was a Portuguese fuel and refined petrochemical distributor established in 1957 and based in Lisbon,[117] owned by Sonangol (49%) and Petrogal (51%).