In developed countries, the incidence of hepatitis E virus (HEV) infection and the resulting seroprevalence are uncertain. Published estimates of seroprevalnce in these populations range from 0.26% to 31%, which may in part reflect the variety of assays used by different studies. This study compared the performance of two commercial assays (Genelabs [Singapore] and Wantai ‘Beijing, China’ HEV IgG EIA kits) and reviewed published estimates of anti-HEV seroprevalence in developed countries. The assays were compared using the WHO anti-HEV reference serum, sera from UK-acquired cases of genotype 3 HEV infections and 500 UK blood donor sera. The PE2 assay was found to be more sensitive than the GL assay (lower limit of detection for HEV IgG 0.25 vs. 2.5 WHO units/ml); it was positive in more sera from proven cases (98% vs. 56%), remained positive for longer post infection and resulted in a substantially higher estimate of seroprevalence in blood donors (16.2% vs. 3.6%). these results suggest that published studies of HEV seroprevalence using the GL assay have underestimated the true figure and that a properly validated method is required to make meaningful comparisons of HEV seroprevalence between populations. J. Med. Virol. 82: 799–805, 2010. © 2010 Wiley-Liss, Inc.