A fluid permeable heater assembly for aerosol-generating systems comprises a substrate (1) comprising an opening (100) through the substrate, an electrically conductive substantially flat filament arrangement (2) arranged over the opening, and clamping means (3) mechanically fixing the filament arrangement to the substrate. The clamping means are electrically conductive and serve as electrical contacts for providing a heating current through the filament arrangement. The invention also relates to a method for assembling a fluid permeable heater.
