Municipality Polzela, which is part of the Savinjska statistical region, measures 34 km2; this ranks it 163rd among Slovene municipalities.
Statistical data for 2019 reveal the following:
In the middle of 2019 about 6,220 people (about 3,040 men and 3,190 women) were living in the municipality, which ranks Polzela 85th among Slovene municipalities. The population density was 183 people per square kilometre, which was higher than the national average of 103 people per square kilometre.
The number of live births was lower than the number of deaths, which means that natural increase per 1,000 population in the municipality was negative. It was -4.7 (in Slovenia -0.6). The number of people who moved from the municipality was lower than the number of people who moved into the municipality, so net migration per 1,000 population in the municipality was positive. It was 15.3. The sum of natural increase and net migration per 1,000 population in the municipality was positive. It was 10.6 (in Slovenia 7.2).
The mean age of people in Polzela was 43.4 years, which was the same as the national average.
As in most Slovene municipalities, in Polzela the number of old people was higher than the number of young people: there were 124 people, aged 65 or more, per 100 people aged 0–14. This ratio shows that the value of the ageing index was lower than the national average of 133. It also shows that the mean age of people in Polzela is growing more slowly than in Slovenia as a whole. Data by sex show that the ageing index for women was in all municipalities except in two (Jezersko and Loški Potok) higher than the ageing index for men. In Polzela – as in most Slovene municipalities – more women were 65+ years old than 14 or less; for men the situation was the same.
Polzela had 1 kindergarten. It was attended by 257 children or 90% of all children aged 1–5, which was more than the national average of 81%. In the school year 2019/20 elementary schools in Polzela were attended by about 640 pupils, while various upper secondary schools were attended by about 240 pupils. There were 38 students and 8 graduates per 1,000 people in the municipality; in Slovenia the averages were 37 per 1,000 and 8 per 1,000, respectively.
Among people aged 15–64 (i.e. working age population) about 67% were persons in employment (i.e. persons in paid employment or self-employed persons), which is more than the national average (66%).
In Polzela, average monthly gross earnings per person employed by legal persons were about 17% lower than the annual average of monthly earnings for Slovenia; net earnings were about 15% lower.
Among 100 inhabitants in the municipality, 57 had a passenger car. The car was on average 10 years old.
In 2019, 325 kg of municipal waste per person was collected in Polzela, which is 34 kg less than on average in Slovenia.