Diagnostic assays that use polymerase chain reaction (PCR) methods are increasingly available to veterinarians. Psittacine beak and feather disease virus (family Circoviridae, genus Circovirus) is a pathogen of clinical importance for which PCR assays have been developed. Several laboratories offer this diagnostic assay in the United States; however, there is little information on the sensitivity, specificity, or accuracy of these assays. In this study, known positive (n  =  10) and negative (n  =  10) samples were sent to 5 commercial laboratories. Accuracy was 100% for 2 laboratories, 95% for 2 laboratories, and 71% for 1 laboratory; the accuracy of the latter laboratory was affected because of a specificity of 20%. These results suggest that although the results from most laboratories are highly accurate, both false-positive and false-negative results are occasionally reported by at least 2 laboratories. These results also suggest that at least 1 laboratory may be generating large numbers of false-positive results.