The country is fairly homogeneous linguistically and religiously. Native Portuguese are ethnically a combination of pre-Celts and Celts along with some other minor contributions by Romans, Germanic (Visigoths, Subi, Buri), some Jews and Moors (mostly Berbers and some Arabs).

In the 2001 census, the population was 10,356,117, of which 51% was female, 48% was male. Portugal, long a country of emigration, has now become a country of net immigration, and not just from the former Indian and African colonies; by the end of 2003, legal immigrants represented about 5% of the population, and the largest communities were from Brazil, Ukraine, Romania, Cape Verde, Angola, Russia, Guinea-Bissau and Moldova with other immigrants from parts of Latin America, China and Eastern Europe. The great majority of Portuguese are Roman Catholic, though a large percentage consider themselves non-practicing, especially in urban areas. The biggest metropolitan areas are Lisbon, Porto, Braga, Coimbra, Setúbal and Aveiro.