A method of making drainable ostomy pouch outlet includes the steps of attaching a single-piece closure device on a downwardly extending outlet portion of the pouch and trimming side peripheries of the single-piece closure device to provide at least two separate closure members. The single-piece closure device may include at least one transversely-extending cut-line and/or at least one cut-out portions, which may be arranged to form at least two separate closure members on the outlet portion after the step of trimming.