There is provided an aerosol-forming cartridge for an electrically operated aerosol-generating system. The aerosol-forming cartridge includes a base layer including at least one cavity and at least one aerosol-forming substrate held in the at least one cavity. A protective foil is removably attached to the base layer and is arranged to substantially hermetically seal the at least one aerosol-forming substrate within the at least one cavity prior to use of the aerosol-forming cartridge.