Bas-Armagnac ("Lower Armagnac"; ) is one of the three plantation areas in the Armagnac area of France where grapes for the distillation of the Armagnac eau-de-vie can be cultivated.
57% of the Armagnac AOC's vineyards are within Bas-Armagnac. The Bas-Armagnac AOC was created in 1936, alongside its parent AOC (Armagnac) and its sibling AOCs (Armagnac-Ténarèze and Haut-Armagnac).
Bas-Armagnac extends over the Landes and Gers departments. It lies in the west, beside Armagnac-Ténarèze, an undulating area. The grapes grow in acidic, argillaceous and stony ground. Iron rust colors parts of the soil and these spots are called . Major towns in the Armagnac region include Eauze, Cazaubon and Nogaro.