Municipality Mozirje, which is part of the Savinjska statistical region, measures 54 km2; this ranks it 127th among Slovene municipalities.
Statistical data for 2021 reveal the following:
In the middle of 2021 about 4,270 people (about 2,110 men and 2,160 women) were living in the municipality, which ranks Mozirje 119th among Slovene municipalities. The population density was 80 people per square kilometre, which was lower than the national average of 104 people per square kilometre.
The number of live births was higher than the number of deaths, which means that natural increase per 1,000 population in the municipality was positive. It was 2.1 (in Slovenia -2.0). 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 35.4. The sum of natural increase and net migration per 1,000 population in the municipality was positive. It was 37.5 (in Slovenia -0.9).
The mean age of people in Mozirje was 43.5 years, which was lower than the national average (43.8).
As in most Slovene municipalities, in Mozirje the number of old people was higher than the number of young people: there were 133 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 139. It also shows that the mean age of people in Mozirje 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 five (Črna na Koroškem, Dobrovnik/Dobronak, Jezersko, Loški Potok in Mislinja) higher than the ageing index for men. In Mozirje – as in most Slovene municipalities – more women were 65+ years old than 14 or less; for men the situation was the same.
Mozirje had 1 kindergarten, which was attended by 195 children. Of all children in the municipality aged 1–5, 81% were included in kindergartens, which was the same as the national average. In the school year 2021/22 elementary schools in Mozirje were attended by about 400 pupils, while various upper secondary schools were attended by about 190 pupils. There were 42 students and 10 graduates per 1,000 people in the municipality; in Slovenia the averages were 39 per 1,000 and 8 per 1,000, respectively.
Among people aged 15–64 (i.e. working age population) about 72% were persons in employment (i.e. persons in paid employment or self-employed persons), which is more than the national average (67%).
In Mozirje, average monthly gross earnings per person employed by legal persons were about 15% lower than the annual average of monthly earnings for Slovenia; net earnings were about 13% lower.
Among 1,000 inhabitants in the municipality, 582 had a passenger car. The car was on average 11 years old.
In 2021, 312 kg of municipal waste per person was collected in Mozirje, which is 53 kg less than on average in Slovenia.