It is expected that the ruling center-left Socialists might win.
Opinion polls indicate the Socialists will come top with 36.5% - 38.8% of the vote but will need one or more parties to back them to stay in government. Costa’s minority government has been backed by two left parties since 2015.
"I’m voting for Costa again. He’s done well for us. He represented the people, defended the people, and I can only hope he does more of the same if he wins," 81-year old Fatima Abreu said at a central Lisbon polling station early on Sunday.
As it was reported by Reuters, Luis Alberto Lopes Brazao, a 46-year old homeless man, agreed. "I’m from a poor family and I’m struggling... But I trust this government," he said after voting for the Socialists.
It is also expected that the main opposition of the social-democrats party, which got the 30% voters support according to the last polls, will lose its places in the parliament.