They added that PKW expects the last election protocol will be registered between 2 pm and 3 pm.
Earlier, PKW head Wieslaw Kozielewicz said that the official election results would be known this evening, between 6 pm and 8 pm.
According to results from 90.8 pct of polling stations published on the state election website, Poland's ruling coalition United Right, led by the conservative but socially-oriented Law and Justice (PiS) party (PiS), received 44.57 percent of the national vote in the ballot.
The ruling party's main contender, the centrist Civic Coalition (KO), led by the Civic Platform (PO), received 26.65 percent of the vote.
The Left, a coalition of three left-wing parties, running under the Democratic Left Alliance (SLD) party banner, was supported by 12.27 percent.
The agrarian Polish People's Party (PSL), which ran together with the right-wing Kukiz'15 movement, was supported by 8.63 percent of voters.
The far-right Confederation was backed by 6.76 percent of voters in the Ipsos exit poll. (PAP)
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