The 2008 CIA estimate of Sierra Leone’s population is 6,294,774. Freetown, with an estimated population of 1,070,200, is the capital, largest city and the hub of the economy, commercial, educational and cultural centre of the country. Bo is the second city. Other cities with a population over 100,000 are Kenema, Koidu Town and Makeni.

Although English is the official language spoken at schools and government administration, Krio (language derived from English and several African languages and native to the Sierra Leone Krio people) is the lingua franca spoken in virtually all parts of Sierra Leone. The Krio language unites all the different ethnic groups, especially in their trade and interaction with each other.

According to the World Refugee Survey 2008, published by the U.S. Committee for Refugees and Immigrants, Sierra Leone had a population of 8,700 refugees and asylum seekers at the end of 2007. Nearly 20,000 Liberian refugees voluntarily returned to Liberia over the course of 2007. Of the refugees remaining in Sierra Leone, nearly all were Liberian.