A coated paper-based substrate for manufacturing a container and a method for preparing the same. The coated paper-based substrate comprises a cellulosic fiber-based substrate coated on a first surface with a coating A and coated on a second surface with a coating B. The coating A comprises at least one layer of an extruded or laminated polymeric film or of a laminated foil. The coating B comprises at least one layer obtained by applying an aqueous dispersion of at least one polymer or copolymer capable of providing a water and/or moisture barrier to the second surface of the paper-based substrate once coated. The extruded or laminated polymeric film and the polymer or copolymer of the aqueous dispersion are different. The coating A and the coating B are heat sealable to each other.