Sils im Engadin/Segl has a population () of . , 38.5% of the population are resident foreign nationals. In 2015, 144 people or 18.9% of the population were born in Portugal, 42 or 5.5% of the population were born in Germany and 63 or 8.3% of the population were born in Italy. Over the last 4 years (2010–2014) the population has changed at a rate of 2.13%. The birth rate in the municipality, in 2014, was 15.7, while the death rate was 1.3 per thousand residents.