This document specifies a method for the detemination of fumonisin B1 (FB1) and fumonisin B2 (FB2) in maize based foods using high performance liquid chromatography (HPLC) and immunoaffinity clean-up, see [1], [2],[3].The method has been successfully validated in a collaborative study according to AOAC Guidelines for collaborative study procedures [4] to validate characteristics of a method of analysis for the determination of fumonisins in maize flour and corn flakes containing 323 μg/kg to 1414 μg/kg FB1 and 90 μg/kg to 558 μg/kg FB2.