The population of Lesotho in 2003 was estimated by the United Nations at 1,802,000, which placed it as number 143 in population among the 193 nations of the world. In that year approximately 5% of the population was over 65 years of age, with another 40% of the population under 15 years of age. There were 87 males for every 100 females in the country in 2003. According to the UN, the annual population growth rate for 2000–2005 is 0.14%, with the projected population for the year 2015 at 1,713,000. The population density in 2002 was 73 per sq km (188 per sq mi).
Some 70% of the total population lives in the fertile lowlands, where the land can be most readily cultivated; the rest is scattered in the foothills and the mountains. It was estimated by the Population Reference Bureau that 28% of the population lived in urban areas in 2001. The capital city, Maseru, had a population of 373,000 in that year. Other large towns are Leribe, Berea, and Mafeteng. According to the United Nations, the urban population growth rate for 2000–2005 was 4.6%.
The prevalence of AIDS/HIV has had a significant impact on the population of Lesotho. The United Nations estimated that 30.1% of adults between the ages of 15–49 were living with HIV/AIDS in 2001. The AIDS epidemic causes higher death and infant mortality rates, and lowers life expectancy.