CBOS survey: Stabilization of KO, decline of PiS and growth of left-wing parties

Stabilization at the top, declines and increases in the middle of the pack

As CBOS emphasizes, September is the second month in a row in which the Civic Coalition maintains a stable level of support. Compared to August, the group recorded a minimal increase of 0.3 percentage points.

However, it is difficult to talk about a significant improvement in KO ratings - comment the authors of the study.

Law and Justice is doing much worse. Jarosław Kaczyński's party lost 1.5 percentage points compared to the previous month and gained 15 percent. support. This is PiS's lowest result since the 2023 parliamentary elections.

In third place was Confederation, which can boast of an increase in support by 1.8 percentage points - currently 14.8 percent would vote for this party. respondents.

Who else would cross the threshold?

The Confederation of the Crown of Poland (7.8%), Razem (6.1%) and Nowa Lewica (5.9%) would also enter the Sejm. It is worth paying attention to the growth of both left-wing parties - Razem gained 1.7 percentage points, and Nowa Lewica as much as 2.1 percentage points compared to August.

Below the electoral threshold were, among others: Rozwoju Plus, the grouping of former Prime Minister Mateusz Morawiecki (3.7%), Polish People's Party (2.5%), Polska 2050 RP (0.8%) and Unia Centrum (0.1%). Other parties were chosen by 0.7 percent. respondents.

Turnout and the undecided

73.9% of people declared their participation in the elections. respondents – this is an almost identical result as in August. 14.3 percent voters still do not know who they will vote for, and 2.2 percent refused to answer this question.

About the study

The CBOS survey was conducted on September 7-9, 2026 on a representative sample of 1,001 adult Poles. The survey was carried out using telephone interviews (CATI – 80%) and online interviews (CAWI – 20%). The results were calculated using the so-called electoral weight, taking into account declarations of participation in elections and party preferences.