Anion exchange (AEX) is a common downstream purification operation for biotechnology products manufactured in cell culture such as therapeutic monoclonal antibodies (mAbs) and Fc-fusion proteins. We present a head-to-head comparison of the viral clearance efficiency of AEX adsorbers and column chromatography using the same process fluids and comparable run conditions. We also present overall trends from the CDER viral clearance database. In our comparison of multiple brands of resins and adsorbers, clearance of three model viruses (PPV, X-MuLV, and PR772) was largely comparable, with some exceptions which may reflect run conditions that had not been optimized on a resin/membrane specific basis. (c) 2013 American Institute of Chemical Engineers Biotechnol. Prog., 30:124-131, 2014