Originally, only researchers and institutions to which they belonged had the interest and ability to adopt the new system and register domains under .br.

As such, even before Brazil officially connected to the Internet in 1991, the .br domain was used to identify the machines participating in networks already in use by academics.

In 2005, CGI.br created its own executive arm, the Brazilian Network Information Center (Portuguese: Núcleo de Informação e Coordenação do Ponto BR, or simply NIC.br),[4] which currently serves in both administrative and operational capacity for the registry.

The registration of domains including non-ASCII Portuguese characters (à, á, â, ã, é, ê, í, ó, ô, õ, ú, ü and ç) is accepted since 2005.

[8] In late 2000, the Brazilian Internet Steering Committee reported abuse in this system, and called for all institutions directly under .br to be moved to .edu.br – so, for example, ufrj.br would become ufrj.edu.br.

[17] In late 2024, legislation regulating online gambling in Brazil – usually referred to simply as "bets" in the country – was passed.

There are multiple agencies registered directly under .br, as second-level domains, that are not higher education or research institutions.

Again, this list may not be exhaustive: As of September 2024, .BR is the 9th most used TLD in the world and the 6th most used ccTLD, accounting for approximately 1.5% of all domain names.

[1]As of 9 September 2024, Registro.br's statistics page reported the following:[1] The "Education" category also includes 1,207 (0.02% of the total) custom second-level domains registered directly under .BR – for example, the National Observatory at ON.BR.