Wettswil am Albis has a population (as of 31 December 2018) of . s of 2007[ [update]], 11.3% of the population was made up of foreign nationals. Over the last 10 years the population has grown at a rate of 21.4%. Most of the population (as of 2000[ [update]]) speaks German (91.7%), with French being second most common ( 1.4%) and Italian being third ( 1.3%).