A method for manufacturing a flexible container including a body, a base including an emptying spout and a cover including a filling spout, includes: cutting, from a sheet of flexible material, four main panels of the body and the base and four cover panels, each main panel having a square or rectangular shape having four sides, the bottom side being extended by an approximately trapezoidal extension, whose end towards the bottom is extended by a tab, the extension and tab forming the base and emptying spout, each cover panel having a substantially trapezoidal shape with a base towards the bottom and whose end towards the top is extended by a tongue forming the filling spout; forming a fold in each main panel along the top side; fixing the fold to form at least one loop per main panel; assembling and securing together the four main panels and four cover panels.