The invention relates to a rack (21, 27, 28) for supporting electrostatic filter plates (22, 23) of an electrostatic filter (20). The rack (21, 27, 28) is an elongated member comprising a plurality of notches (11) on a longitudinal side of the rack (21, 27, 28) for supporting a plate (22, 23) arranged to a notch (11). The rack (21, 27, 28) further comprises a slot (26) for adhesive arranged to be used at least for attaching the plates (22, 23) to the rack (21, 27, 28). The slot (26) is arranged on the opposite side of the rack (21, 27, 28) than notches (11). There is also an opening (24) in the first group of plates (22) at that point where the plates (22) are aligned with the voltage supply rack (28) but which are not attached to that rack (28). The invention further relates to an electrostatic filter (20) comprising a plurality of racks.