After the first results were announced, Seguro conceded defeat and resigned as Secretary-General of the Party.

[1] Following the narrow victory of the Socialist Party over the coalition between the PSD and the CDS-PP in the European elections on 25 May 2014, many Socialist Party members and supporters considered the result a disappointment and many blamed Seguro for not being a real alternative to the Prime Minister Pedro Passos Coelho (PSD).

On 27 May, António Costa announced that he would seek the leadership of the Socialist Party.

[3] After a bitter meeting of the party leadership members, António Costa included, it was agreed to call a primary election open to supporters of the Socialist Party that would elect the party's candidate for Prime Minister for the following legislative elections in October 2015.

Unlike previous Socialist Party leadership elections, this was the first primary to be open to the general public.