There is provided an electrically heated aerosol-generating device (100) for use with a consumable cartridge (200) comprising a storage portion (202) containing an aerosol-forming substrate and having a fluid permeable internal surface (204) surrounding an open ended passage (208) extending through the cartridge. The device includes a main housing (102) having a cavity (108) for receiving a consumable cartridge, a closure body (110) engageable with the main housing to enclose the cartridge in the cavity,and a heater assembly (300) for heating the cartridge. The heater assembly includes an elongate piercing assembly (302) arranged to extend into the open-ended passage of the cartridge and one or more electric heaters (400) fixed thereto. The piercing assembly has a first hollow shaft portion (304) connected to the main housing and a second hollow shaft portion (324) connected to the closure body. The first and second hollow shaft portions (304, 324) have first and second piercing surfaces(308, 328) at their distal ends for breaking through first and second frangible seals (210, 212) across first and second ends of the open ended passage when the cartridge is enclosed in the cavity. The first and second hollow shaft portions are arranged to extend along the same longitudinal axis and are sized to meet at a junction (330) such that the elongate piercing assembly extends along the entire length of the cavity when the closure body is engaged with the main housing.
