Municipality Mengeš, which is part of the Osrednjeslovenska statistical region, measures 22 km2; this ranks it 197th among Slovene municipalities.
Statistical data for 2023 reveal the following:
In the middle of 2023 about 8,640 people (about 4,330 men and 4,310 women) were living in the municipality, which ranks Mengeš 61th among Slovene municipalities. The population density was 385 people per square kilometre, which was higher than the national average of 105 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 –5.3 (in Slovenia –2.1). 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 11.9. The sum of natural increase and net migration per 1,000 population in the municipality was positive. It was 6.6 (in Slovenia 3.3).
The mean age of people in Mengeš was 42.5 years, which was lower than the national average (44.1).
As in most Slovene municipalities, in Mengeš the number of old people was higher than the number of young people: there were 115 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 145. It also shows that the mean age of people in Mengeš 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 six (Črna na Koroškem, Dobrovnik/Dobronak, Grad, Hodoš/Hodos, Jezersko in Mislinja) higher than the ageing index for men. In Mengeš – as in most Slovene municipalities – more women were 65+ years old than 14 or less; for men the situation was the same.
Mengeš had 3 kindergartens, which were attended by 399 children. Of all children in the municipality aged 1–5, 83% were included in kindergartens, which was the same as the national average. In the school year 2023/24 elementary school in Mengeš was attended by about 860 pupils, while various upper secondary schools were attended by about 350 pupils. There were 36 students and 7 graduates per 1,000 people in the municipality; in Slovenia the averages were 38 per 1,000 and 8 per 1,000, respectively.
Among people aged 15–64 (i.e. working age population) about 73% were persons in employment (i.e. persons in paid employment or self–employed persons), which is more than the national average (69%).
In Mengeš, average monthly gross earnings per person employed by legal persons were about 5% lower than the annual average of monthly earnings for Slovenia; net earnings were about 5% lower.
Among 1,000 inhabitants in the municipality, 541 had a passenger car. The car was on average 11 years old.
In 2023, 531 kg of municipal waste per person was collected in Mengeš, which is 153 kg more than on average in Slovenia.