The arrondissement of Tournon-sur-Rhône was created in 1800.[4] At the January 2017 reorganization of the arrondissements of Ardèche, it gained five communes from the arrondissement of Privas and it lost three communes to the arrondissement of Largentière and eight communes to the arrondissement of Privas.[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 Tournon-sur-Rhône were, as of January 2015:[6]