[3] Under the newly promulgated 2018 constitution and following the new administrative division, the senate similarly to the national assembly saw its number of seats reduced.

In each of the country's 18 provinces, two Senators (one Hutu and one Tutsi) are chosen by electoral colleges of communal councilors.

Three Senators represent the Twa ethnic group and additional members may be co-opted to meet the 30% gender representation quota for women.

The 1962 constitution of the Kingdom of Burundi provided for the creation of the Senate at the discretion of the Mwami and the National Assembly.

Senate members were indirectly elected on 29 July 2005 by an electoral college of commune and provincial councils.

On 19 August 2005, the Senate and National Assembly (acting as an Electoral College) elected Pierre Nkurunziza president of the republic.

On 25 June 2015, he fled the country saying he felt threatened after opposing President Nkurunziza's bid for a third term.