An apparatus for an electronic aerosol provision system (10). The apparatus may comprise a replaceable cartridge (30) for the electronic aerosol provision system or may comprise a fixed component of a re-fillable or disposable electronic aerosol provision system. The apparatus comprises a reservoir (38) for a source liquid and a carrier module (160) supported within the reservoir. The carrier module defines an airflow path (120) within the reservoir and comprises a heating element (103) supported in the airflow path for generating an aerosol from the source liquid and first and second mounting parts (101, 102) which cooperatively engage to support the heating element. The first and second mounting parts of the carrier module cooperatively engage at an interface which extends in a direction that is substantially parallel to a direction along which air flows in the airflow path when the apparatus is in normal use. A gap (200) between the first and second mounting parts may provide a capillary channel (200) for drawing source liquid to the heating element from the reservoir heating during use.
