Migration continues to transform Belize's population. About 16% of Belizeans live abroad, while immigrants constitute approximately 15% of Belize's population. Belizeans seeking job and educational opportunities have preferred to emigrate to the United States rather than former colonizer Great Britain because of the United States' closer proximity and stronger trade ties with Belize. Belizeans also emigrate to Canada, Mexico, and English-speaking Caribbean countries. The emigration of a large share of Creoles (Afro-Belizeans) and the influx of Central American immigrants, mainly Guatemalans, Salvadorans, and Hondurans, has changed Belize's ethnic composition. Mestizos have become the largest ethnic group, and Belize now has more native Spanish speakers than English or Creole speakers, despite English being the official language. In addition, Central American immigrants are establishing new communities in rural areas, which contrasts with the urbanization trend seen in neighboring countries. Recently, Chinese, European, and North American immigrants have become more frequent.

Immigration accounts for an increasing share of Belize's population growth rate, which is steadily falling due to fertility decline. Belize's declining birth rate and its increased life expectancy are creating an aging population. As the elderly population grows and nuclear families replace extended households, Belize's government will be challenged to balance a rising demand for pensions, social services, and healthcare for its senior citizens with the need to reduce poverty and social inequality and to improve sanitation.