The party now will not be able to form a government on its own.
The PiS party is followed by the Civic Coalition opposition party with 30.7% of the vote, the Third Way centrist party with 14.4% of the vote and the Confederation Liberty and Independence party with 7.16% of the vote, according to the electoral commission.
The current distribution of seats in the Polish parliament indicates that the opposition bloc, consisting of the Civic Coalition, the Third Way and the Left parties, may receive over half of the seats in the Sejm, the parliament's lower house, and form a government if a coalition is established.
Kaczynski's ruling party has not gained enough seats and will operate without a majority in the Senate, the parliament's upper house, the electoral commission said. The ruling party's senators, including Deputy Health Minister Waldemar Kraska, former Senate Speaker Stanislav Karchevsky and Deputy Defense Minister Wojciech Skurkiewicz, will remain in the Senate.
The electoral commission also said that the PiS won only 34 out of 100 seats in the upper house. The party obtained 48 seats after the 2019 parliamentary elections. The opposition bloc received the overwhelming advantage in the upper house and will be represented by 66 senators, according to the commission.
Meanwhile, the Civic Coalition is planning to nominate former European Council President Donald Tusk for the post of prime minister, the opposition party's vice chairman, Cezary Tomczyk, said.
"Donald Tusk is a natural candidate for the post of prime minister ... We want the coalition talks to take place as soon as possible. We are in touch with the leaders of other groups," Tomczyk said on air of a Polish radio broadcaster.
Voter turnout in the Polish parliamentary elections has hit a record high of 74.38% since 2019, the electoral commission added after processing 100% of the ballots.