Abstract: An aerosol-generating device is provided, including a housing containing or configured to receive an aerosol-forming substrate; an outlet formed in the housing, wherein in use aerosol generated from the aerosol-forming substrate is delivered through the outlet, wherein the housing includes a first wall surrounding the outlet and a second wall surrounding the first wall such that an open-ended annular recess is defined between the first and second walls, the annular recess being suitable for retaining a compliant mouthpiece cover to the housing. In use, the mouthpiece cover is placed into a user's mouth in order to directly inhale an aerosol generated by the aerosol-generating device. There is also provided a removable mouthpiece cover for an electrically operated smoking device, including a compliant tubular portion defining a central bore and a filter portion covering the bore of the filter portion.