According to the 2011 census South Sikkim district has a population of 146,742, roughly equal to the nation of Saint Lucia. This gives it a ranking of 600th in India (out of a total of 640). The district has a population density of . Its population growth rate over the decade 2001-2011 was 11.57%. South Sikkim has a sex ratio of 914 females for every 1000 males, and a literacy rate of 82.06%.