Ruswil has a population (as of ) of . , 4.6% of the population was made up of foreign nationals. Over the last 10 years the population has grown at a rate of 2.8%. Most of the population () speaks German (95.8%), with Italian being second most common ( 0.7%) and Albanian being third ( 0.6%). In the
2023 Swiss federal elections, the most popular party was the Centre (a merger of the former
CVP and the
Conservative Democratic Party) which received 39.7%, followed by the
SVP (29.9%),
FDP (11.5%),
SPS (7.8%),
Green Liberal Party (4.4%),
Greens (4.3%) and others (2.3%). In the 2007 Swiss federal election the most popular party was the
CVP which received 42.5% of the vote. The next three most popular parties were the
SVP (24.4%), the
FDP (16.7%) and the
SPS (7%). The age distribution in Ruswil is; 1,690 people or 26.2% of the population is 0–19 years old. 1,726 people or 26.7% are 20–39 years old, and 2,169 people or 33.6% are 40–64 years old. The senior population distribution is 628 people or 9.7% are 65–79 years old, 200 or 3.1% are 80–89 years old and 47 people or 0.7% of the population are 90+ years old. In Ruswil about 73% of the population (between age 25–64) have completed either non-mandatory
upper secondary education or additional higher education (either university or a
Fachhochschule). there are 2,136 households, of which 529 households (or about 24.8%) contain only a single individual. 338 or about 15.8% are large households, with at least five members. 51.5% of the population of the municipality were employed in some capacity. At the same time, females made up 39.5% of the workforce. the religious membership of Ruswil was; 5,226 (83.5%) were Roman Catholic, and 475 (7.6%) were Protestant, with an additional 21 (0.34%) that were of some other Christian faith. There are 73 individuals (1.17% of the population) who are Muslim. Of the rest; there were 11 (0.18%) individuals who belong to another religion (not listed), 163 (2.6%) who do not belong to any organized religion, 293 (4.68%) who did not answer the question. ==References==