The U.S. government estimates the country’s total population at 69.0 million (midyear 2020 estimate). The 2010 population census, the most recent available, indicated 93 percent of the population is Theravada Buddhist and 5 percent Muslim. NGOs, academics, and religious groups state that 85 to 95 percent of the population is Theravada Buddhist and 5 to 10 percent Muslim. Other groups, including animists, Christians, Confucians, Hindus, Jews, Sikhs, and Taoists, constitute the remainder of the population.

Most Buddhists incorporate Hindu and animist practices into their worship. The Buddhist clergy (sangha) consists of two main schools of Theravada Buddhism: Mahanikaya and Dhammayuttika. The former is older and more prevalent within the monastic community.

Islam is the dominant religion in three of the four southernmost provinces (Narathiwat, Yala, and Pattani) near the Malaysian border, commonly referred to as the Deep South. The majority of Muslims in those provinces are ethnic Malay, but the Muslim population nationwide also includes descendants of immigrants from South Asia, China, Cambodia, and Indonesia, as well as ethnic Thai. Statistics provided by the Religious Affairs Department (RAD) of the Ministry of Culture indicate that 99 percent of Muslims are Sunni.

The majority of ethnic Chinese and Vietnamese practice either Mahayana or Theravada Buddhism. Many ethnic Chinese, as well as members of the Mien hill tribe, also practice forms of Taoism.

The majority of Christians are ethnic Chinese, and more than half of the Christian community is Roman Catholic.