The arrondissement of Bazas was created in 1800. The subprefecture was moved to Langon in 1926.[4] At the May 2006 reorganisation of the arrondissements of Gironde, it gained the cantons of Cadillac and Podensac from the arrondissement of Bordeaux.[4][5]
As a result of the reorganisation of the cantons of France which came into effect in 2015, the borders of the cantons are no longer related to the borders of the arrondissements. The cantons of the arrondissement of Langon were, as of January 2015:[6]