Municipality Trbovlje, which is part of the Zasavska statistical region, measures 58 km2; this ranks it 122nd among Slovene municipalities.
Statistical data for 2020 reveal the following:
In the middle of 2020 about 16,010 people (about 7,870 men and 8,140 women) were living in the municipality, which ranks Trbovlje 32nd among Slovene municipalities. The population density was 276 people per square kilometre, which was higher than the national average of 104 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 -8.5 (in Slovenia -2.5). 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 2.2. The sum of natural increase and net migration per 1,000 population in the municipality was negative. It was -6.3 (in Slovenia 6.2).
The mean age of people in Trbovlje was 46.2 years, which was higher than the national average (43.6).
As in most Slovene municipalities, in Trbovlje the number of old people was higher than the number of young people: there were 180 people, aged 65 or more, per 100 people aged 0–14. This ratio shows that the value of the ageing index was higher than the national average of 136. It also shows that the mean age of people in Trbovlje is growing more rapidly than in Slovenia as a whole. Data by sex show that the ageing index for women was in all municipalities except in three (Dobrovnik/Dobronak, Jezersko in Loški Potok) higher than the ageing index for men. In Trbovlje – as in most Slovene municipalities – more women were 65+ years old than 14 or less; for men the situation was the same.
Trbovlje had 6 kindergartens, which were attended by 534 children. Of all children in the municipality aged 1–5, 76% were included in kindergartens, which was less than national average of 81%. In the school year 2020/21 elementary schools in Trbovlje were attended by about 1,280 pupils, while various upper secondary schools were attended by about 420 pupils. There were 32 students and 6 graduates per 1,000 people in the municipality; in Slovenia the averages were 39 per 1,000 and 7 per 1,000, respectively.
Among people aged 15–64 (i.e. working age population) about 61% were persons in employment (i.e. persons in paid employment or self-employed persons), which is less than the national average (66%).
In Trbovlje, average monthly gross earnings per person employed by legal persons were about 3% lower than the annual average of monthly earnings for Slovenia; net earnings were about 3% lower.
Among 1,000 inhabitants in the municipality, 504 had a passenger car. The car was on average 10 years old.
In 2020, 396 kg of municipal waste per person was collected in Trbovlje, which is 41 kg more than on average in Slovenia.