The major ethnic groups are - Punjabis (44.68% of the population), Pashtuns (15.42%), Sindhis (14.1%), Seraikis (10.53%), Muhajirs (7.57%), Balochis (3.57%) and others (4.66%). As of November 2007, about 2 million registered Afghan refugees remain in Pakistan as a result of the ongoing war and instablity in Afghanistan.

Primary mother tongue language usage largely corresponds to ethnic groups. Despite being a native language of a relatively small minority, Urdu is the national language and lingua franca of Pakistan, while English is the official language, used in the Constitution and widely used by corporate businesses, the educated urban elite, and most universities. Punjabi is spoken by over 60 million people, but has no official recognition in the country.

The demographics of religion in Pakistan were significantly influenced in 1947 by the movement of Muslims to Pakistan, and Hindus and Sikhs to India. Census data indicates that 96% of the population are Muslims, (nearly 77% are Sunni Muslims and 20% are Shi'a Muslims according to CIA estimates[4]). Minority religions include Hinduism (1.85%), Christianity (1.6%), as well as much smaller numbers of Sikhs (Around 0.04%), Parsis, Ahmadis, Buddhists, Jews, and Animists (mainly the Kalasha of Chitral). Pakistan is the second most populous Muslim-majority country[76] and also has the second largest Shi'a population in the world.