The vast majority of the Pashtuns are found in the traditional Pashtun homeland, located in an area south of the Amu Darya in Afghanistan, and west of the Indus River in Pakistan, which includes Khyber Pakhtunkhwa and the northern part of Balochistan. Additional Pashtun communities are located in western and northern Afghanistan, the Gilgit–Baltistan and Kashmir regions, and northwestern Punjab province (Mianwali and Attock), Pakistan. There are also sizeable Muslim communities in India, which are of largely Pashtun ancestry. Throughout the Indian subcontinent, they are often referred to as Pathans. Smaller Pashtun communities are found in the countries of the Middle East, such as in the Khorasan Province of Iran, the Arabian Peninsula, Europe, North America, and Australia.
Important metropolitan centres of Pashtun culture include Peshawar, Kabul, Quetta, Kandahar, Mardan, Mingora, and Jalalabad. In Pakistan, the city of Karachi in Sindh province has the largest Pashtun diaspora communities in the world, with as much as 7 million Pashtuns living in Karachi according to some estimates. Several cities in Pakistan's Punjab province also have sizeable Pashtun populations, in particular Lahore.
About 15% of Pakistan's nearly 200 million population is Pashtun. In Afghanistan, they are the largest ethnic group and make up between 42–60% of the 32.5 million population. The exact figure remains uncertain in Afghanistan, which is also affected by the 1.3 million or more Afghan refugees that remain in Pakistan, a majority of which are Pashtuns. Another one million or more Afghans live in Iran. A cumulative population assessment suggests a total of around 49 million individuals all across the world.
A prominent institution of the Pashtun people is the intricate system of tribes. The Pashtuns remain a predominantly tribal people, but the trend of urbanisation has begun to alter Pashtun society as cities such as Kandahar, Peshawar, Quetta and Kabul have grown rapidly due to the influx of rural Pashtuns. Despite this, many people still identify themselves with various clans.
The tribal system has several levels of organisation: the tribe, tabar, is divided into kinship groups called khels, in turn divided into smaller groups (pllarina or plarganey), each consisting of several extended families called kahols. Pashtun tribes are divided into four 'greater' tribal groups: the Sarbani, the Bettani, the Gharghashti, and the Karlani.