Andrzej Duda won 50.4% of the vote ahead of Rafal Trzaskowski (49.6%), according to an Ipsos poll, in an election with a very high voter turnout of 68.9%.
The first official results of the Polish presidential election were expected on Monday morning.
The outcome of this second round will be decisive for the future of the government of the conservative and nationalist Law and Justice (PiS) party, which its detractors accuse of reversing the democratic freedoms acquired three decades ago at the fall of communism.
The vote was to take place in May - at the time Mr. Duda was leading the voting intentions - but it had to be postponed due to the pandemic caused by the new coronavirus.
In the first round, on June 28, Mr. Duda came first with 43.5% of the vote and Mr. Trzaskowski second with 30.4%.
Eurasia Group, a political risk consultancy, noted just before the vote that Mr. Trzaskowski needed to mobilize very disparate parts of the electorate.
On the other hand, Mr. Duda could count on the mobilization of voters in rural Poland.
With AFP and Reuters
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