[2] The Left Bloc (BE), despite predictions by opinion polls, achieved its best result in history,[3] with more than 10 percent of the vote, becoming the third largest parliamentary group.

[3] Passos Coelho was asked, by the President of the Republic, to form a minority government that took the oath of office on October 30, 2015.

After the PSD/CDS–PP government was sworn in, a series of austerity policies, following the bailout deal, were enacted and created several backlash and protests.

[5] In September 2012, further austerity policies led to one of the biggest demonstrations against a government in Portuguese democracy, with more than 1 million people going out to the streets across the country.

[9] However, CDS – People's Party (CDS-PP) leader, Paulo Portas, criticized the choice of the new minister and announced his "irrevocable" resignation from the government.

[11] A deal was reached a few days later, in which Portas would become deputy prime minister and with more powers on economic affairs.

[13] Despite the Presidential pressures, talks between PSD and PS fell apart and Cavaco Silva was forced to accept the PSD/CDS–PP original deal.

[14] The Social Democrats (PSD) suffered a considerable setback in the 2013 local elections by gathering just 31 percent of the votes and 106 mayors, a drop of 33 cities, while the Socialists (PS) obtained their best result till that date, 150 mayors, a gain of 18, and won almost 37 percent of the votes.

[19] Seguro was elected by a landslide and the results were the following: The 2014 Portuguese Socialist Party prime ministerial primary was held on 28 September 2014.

[21] The results were the following: The start of António Costa's term as PS leader was, however, marred by the arrest of former Socialist Prime Minister José Sócrates on 21 November 2014, due to an inquiry which accused the former prime minister of crimes of tax fraud, money laundering and corruption.

[28] After meeting with all of the parties represented in parliament on 21 July 2015, the President Aníbal Cavaco Silva called the election for 4 October.

[39] After meetings with the various parties, it was decided to hold two face-to-face debates between António Costa and Pedro Passos Coelho in which one would be broadcast on television and the other on radio.

[44][45] Despite Costa's statements during election night, the Socialists, the Left Bloc, the Communists and the Greens started negotiations to form a left-wing majority coalition government.

[46][47] On 19 October 2015, the Secretary-General of the Socialist Party, António Costa, rejected the proposal for a post-election coalition government with the right-wing alliance PàF.

[48] On the next day, Costa said that the Socialist Party would reject in Parliament any government that would be led by Pedro Passos Coelho and supported by the right-wing coalition Portugal Ahead.