Municipality Šempeter - Vrtojba, which is part of the Goriška statistical region, measures 15 km2; this ranks it 205th among Slovene municipalities.

Statistical data for 2012 reveal the following:

In the middle of 2012 about 6,400 people (about 3,200 men and 3,200 women) were living in the municipality, which ranks Šempeter - Vrtojba 82th among Slovene municipalities. The population density was 428 people per square kilometre, which was higher than the national average of 101 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 0.6 (in Slovenia 1.3). 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 0.5. The sum of natural increase and net migration per 1,000 population in the municipality was positive. It was 1.1 (in Slovenia 1.6).

The mean age of people in Šempeter - Vrtojba was 43.7 years, which was higher than the national average (42).

As in most Slovene municipalities, in Šempeter - Vrtojba the number of old people was higher than the number of young people: there were 141 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 118. It also shows that the mean age of people in Šempeter - Vrtojba is growing more rapidly than in Slovenia as a whole. Data by sex show that the ageing index for women was in all Slovene municipalities higher than the ageing index for men. In Šempeter - Vrtojba – as in most Slovene municipalities – more women were 65+ years old than 14 or less; for men the situation was the same.

Šempeter - Vrtojba had 3 kindergartens. They were attended by 273 children or 71% of all children aged 1–5, which was less than the national average of 75%. In the school year 2012/2013 basic schools in Šempeter - Vrtojba were attended by about 560 pupils, while various upper secondary schools were attended by about 250 pupils. There were 50 students and 7 graduates per 1,000 people in the municipality; in Slovenia the averages were 47 per 1,000 and 10 per 1,000, respectively.

Among people aged 15–64 (i.e. working age population) about 56% were persons in employment (i.e. persons in paid employment or self-employed persons), which is less than the national average of 57%.

The registered unemployment rate was 11.4%, which is less than the national average (12%). In contrast to most Slovene municipalities, more men than women were unemployed.

In Šempeter - Vrtojba, average monthly gross earnings per person employed by legal persons were approximately the same as the annual average of monthly earnings for Slovenia; and net earnings about 1% higher.

In 2012, there were 403 dwellings per 1,000 population. About 75% of dwellings had at least three rooms. Average size of dwellings in the municipality was 88 m2.

About every other person in Šempeter - Vrtojba had a car (61 passenger cars per 100 population); cars in this municipality were on average 10 years old.

In 2012, 556 kg of municipal waste per person was collected in Šempeter - Vrtojba, which is 229 kg more than on average in Slovenia.