A sub-assembly for an electronic vapour provision system comprises: a source of liquid for vaporisation; and a vaporizer for vaporising a portion of the liquid for inhalation by a user, the vaporizer comprising: a wick component; and an electrical heating element embedded in the wick component; wherein the wick component comprises a sheet of a porous electrically-insulating material and is arranged to wick liquid from the source of liquid to a surface of the wick component adjacent to the embedded electrical heating element for vaporisation.