Municipality Novo mesto, which is part of the Jugovzhodna Slovenija statistical region, measures 236 km2; this ranks it 20th among Slovene municipalities.
Statistical data for 2021 reveal the following:
In the middle of 2021 about 37,340 people (about 18,800 men and 18,540 women) were living in the municipality, which ranks Novo mesto 6th among Slovene municipalities. The population density was 158 people per square kilometre, which was higher than the national average of 104 people per square kilometre.
The number of live births was the same as the number of deaths, which means that natural increase per 1,000 population in the municipality was positive. It was 1.7 (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 3.5. The sum of natural increase and net migration per 1,000 population in the municipality was positive. It was 5.1 (in Slovenia -0.9).
The mean age of people in Novo mesto was 42.2 years, which was lower than the national average (43.8).
As in most Slovene municipalities, in Novo mesto the number of old people was higher than the number of young people: there were 111 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 Novo mesto 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 Novo mesto – as in most Slovene municipalities – more women were 65+ years old than 14 or less; for men the situation was exactly the opposite.
Novo mesto had 21 kindergartens, which were attended by 1739 children. Of all children in the municipality aged 1–5, 76% were included in kindergartens, which was less than the national average of 81%. In the school year 2021/22 elementary schools in Novo mesto were attended by about 3,940 pupils, while various upper secondary schools were attended by about 1,290 pupils. There were 41 students and 9 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 70% were persons in employment (i.e. persons in paid employment or self-employed persons), which is more than the national average (67%).
In Novo mesto, average monthly gross earnings per person employed by legal persons were about 14% higher than the annual average of monthly earnings for Slovenia; net earnings were about 13% higher.
Among 1,000 inhabitants in the municipality, 582 had a passenger car. The car was on average 10 years old.
In 2021, 344 kg of municipal waste per person was collected in Novo mesto, which is 21 kg less than on average in Slovenia.