According to the Royal Thai Government's 2011 Country Report to the UN Committee responsible for the International Convention for the Elimination of All Forms of Racial Discrimination, available from the Department of Rights and Liberties Promotion of the Thai Ministry of Justice,: 3 62 ethnic communities are officially recognised in Thailand. Twenty million Central Thai (together with approximately 650,000 Khorat Thai) make up approximately 20,650,000 (34.1 percent) of the nation's population of 60,544,937[187] at the time of completion of the Mahidol University Ethnolinguistic Maps of Thailand data (1997).[188]
The 2011 Thailand Country Report provides population numbers for mountain peoples ('hill tribes') and ethnic communities in the Northeast and is explicit about its main reliance on the Mahidol University Ethnolinguistic Maps of Thailand data.[188] Thus, though over 3.288 million people in the Northeast alone could not be categorised, the population and percentages of other ethnic communities circa 1997 are known for all of Thailand and constitute minimum populations. In descending order, the largest (equal to or greater than 400,000) are a) 15,080,000 Lao (24.9 percent) consisting of the Thai Lao (14 million) and other smaller Lao groups, namely the Thai Loei (400–500,000), Lao Lom (350,000), Lao Wiang/Klang (200,000), Lao Khrang (90,000), Lao Ngaew (30,000), and Lao Ti (10,000; b) six million Khon Muang (9.9 percent, also called Northern Thais); c) 4.5 million Pak Tai (7.5 percent, also called Southern Thais); d) 1.4 million Khmer Leu (2.3 percent, also called Northern Khmer); e) 900,000 Malay (1.5%); f) 500,000 Nyaw (0.8 percent); g) 470,000 Phu Thai (0.8 percent); h) 400,000 Kuy/Kuay (also known as Suay) (0.7 percent), and i) 350,000 Karen (0.6 percent).: 7–13 Thai Chinese, those of significant Chinese heritage, are 14% of the population, while Thais with partial Chinese ancestry comprise up to 40% of the population.[189] Thai Malays represent 3% of the population, with the remainder consisting of Mons, Khmers and various "hill tribes". The country's official language is Thai and the primary religion is Theravada Buddhism, which is practised by around 95% of the population.
Increasing numbers of migrants from neighbouring Myanmar, Laos, and Cambodia, as well as from Nepal and India, have pushed the total number of non-national residents to around 3.5 million as of 2009, up from an estimated 2 million in 2008, and about 1.3 million in 2000.[190] Some 41,000 Britons and 20,000 Australians live in Thailand.[191][192]