Flavio Bolsonaro's team struck back with a court filing accusing Lula of "abuse of power" in the mass dissemination of government postings on WhatsApp, retaliating against Lula's petition to have Flavio disqualified before the runoff

Final campaign rallies preceded the second-round vote between Luiz Inácio Lula da Silva and Flávio Bolsonaro on 25 October. Economic priorities, public security and Brazil's international alignment remained central divisions; coverage of the final campaign day does not establish the result.

President Luiz Inácio Lula da Silva faces Senator Flávio Bolsonaro in a closely contested election. A Datafolha survey of 2,506 people, conducted 29 September–1 October across Brazil, put a hypothetical run-off at 48% to 45%; Reuters described the result as a statistical tie within the poll's two-point margin of error. The first round on 4 October produced a run-off between Lula and Flávio Bolsonaro.