The high-stakes race centers on a political rivalry. Outgoing President Carlos Vila Nova, 66, faces party rival Nito Viegas D'Abreu, a current member of parliament backed by former Prime Minister Patrice Trovoada. Two independent candidates are also contesting the vote.

Electoral regulations dictate that if no candidate gains more than 50 percent of Sunday's vote, a second-round run-off will be held on August 9.

National Electoral Commission chief Jeudiger Nascimento voiced concern about low turnout following the close of polls.

He reported that many people had gone to polling stations without casting ballots, though he gave no official figures.

Vila Nova, who was elected president in 2021 with the support of his Independent Democratic Action (ADI) party, has actively campaigned by casting himself as the guarantor of the "political stability of the country".

However, the incumbent has faced heavy criticism for dismissing former Prime Minister Trovoada in January 2025. The controversial executive move was ruled one year later to be contrary to the constitution.

Under the nation's governance structure, the president has a largely ceremonial role, responsible for representation and the promulgation of laws. Most executive powers lie directly with the prime minister.

The Atlantic archipelago, a former Portuguese colony in the Gulf of Guinea, has a population of 200,000 inhabitants. The nation's history is marked by attempted coups, including one in 2022 that was promptly defeated by the military.