Rothrist has a population () of . , 19.1% of the population are foreign nationals.Statistical Department of Canton Aargau -Bereich 01 -Bevölkerung accessed 20 January 2010 Over the last 10 years (1997–2007) the population has changed at a rate of 7%. Most of the population () speaks German (87.4%), with Serbo-Croatian being second most common ( 3.2%) and Italian being third ( 3.1%).Swiss Federal Statistical Office accessed 14-June-2010
