HbA(1c) assay by high-pressure liquid chromatography (HPLC) remains submitted to various analytical interferences. We have evaluated the behaviour of the analyzers G8 (Tosoh Bioscience) and Variant II (BioRad) towards the most common interferences (i.e. labile fraction of HbA(1c), carbamylated hemoglobin, bilirubin, triglycerides, hemoglobin variants). This comparative study showed that the influence of these interferences varied according to the analyzer and depended on various settings such as the chromatographic resolution and the peak integration mode. However, this influence remains limited when strict and analyzer-specific rules of technical validation have been previously determined. The outcome of the study underlines the importance of a detailed interpretation of chromatograms during the biological validation process, and recommends specific procedures in case of interferences, in order to ensure the reliability of HbA(1c) results.