Among religions in Brunei, Sunni Islam is predominant. In 2021, the government census showed that 82.1% of Brunei's population is Muslim. However, other religions also have a considerable foothold in Brunei: 6.7% of the population is Christian and another 6.3% is Buddhist. The remaining 4.9% subscribe to various religions, including indigenous religions.^[1]

Islam is the state religion of Brunei. Freedom of religion and the right to practice privately are nominally guaranteed. Furthermore, some non-Islamic holidays, such as Lunar New Year, Christmas, Vesak day and Gawai Dayak, are recognised. These rights, however, are limited in practice: religious education is controlled, even in the Chinese, Christian and private schools. Brunei's penal code criminalizes efforts to promote religions other than Islam to Muslims or the non-religious, including persuading religious conversion, exposing Muslim children to other faiths, or opposing Islamic authorities. It also punishes those who assist in such acts. These provisions marginalize non-Muslims and non-believers, severely restricting their religious freedom in violation of international human rights standards.^[2] Non-Muslims must be at least 14 years and 7 months old if they want to convert to another religion. A minor will automatically become a Muslim if their parents convert to Islam.^[3]

The state madh'hab of Islam is the Shafi'i school of jurisprudence of Sunni Islam.^[4] Most of Brunei's Muslim population subscribe to the Shafi'i school as well, and Shafi'i is a major source of law for the country.^[4] However, with the Sultan's permission, lawmakers may also consult the other three Sunni schools of fiqh.^[4]

Islam is Brunei's official religion, 82.70 percent of the population is Muslim. There were 362,035 Sunni Muslims in Brunei as of 2021—190,314 men and 171,721 women. 193 people converted to Islam in Brunei–Muara District, 78 in Belait District, 112 in Tutong District, and 15 in Temburong District in 2023. The number of Bruneian converts to Islam has increased ever since Islam became the official religion of the country in 1954. And by 2004, it was recorded that over 16,000 Bruneians had converted to Islam. From 2009 to 2020, there have been 5,884 individuals who have converted to Islam in Brunei.

Almost the entire Hindu community in Brunei is made up of people of Indian origin. The approximate size is a few thousand. There are two Hindu temples in Brunei. According to the 2001 census, 124 of the Hindus are citizens and another 91 are permanent residents. The rest are non-citizens.^[13]

Hinduism is practised by a minority of ethnic Tamils,^[14] which comprises mainly doctors, engineers working in Brunei and others working in the education sector, both at school and university or college level as professors and teachers as well as research personnel.^[15] There is a Nepalese community in Seria, Belait in Brunei, made up of members of the British Army's Brigade of Gurkhas. Historically, they have contributed in ensuring Brunei's autonomy.^[16][17] Brunei's Hindu Welfare Board is a 50 year old Hindu religious organisation with approximately 3,000 members. There are two small Hindu temples in the country,^[18][19] though only one is officially registered under Brunei's government.^[20] The temple is located on the territory of the Gurkha Regiments in Seria, Brunei. This Hindu temple is visited for prayer by the local Hindu and Buddhist communities.^[21][22]

• Freedom of religion in Brunei

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• Puteh, Haji Asri Haji, ed. (2003). Hukum Kanun [Kanun Law] (in Malay). Brunei: Dewan Bahasa dan Pustaka.
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