Posttranslational modifications of immunoglobulins have been a topic of great interest and have been repeatedly reported as a major factor in disease pathology. Cost‐effective, reproducible, and high‐throughput (HTP) isolation of immunoglobulins from human serum is vital for studying the changes in protein structure and the following understanding of disease development. Although there are many methods for the isolation of specific immunoglobulin classes, only a few of them are applicable for isolation of all subtypes and variants. Here, we present the development of a scheme for fast and simultaneous affinity purification of α (A), γ (G), and μ (M) immunoglobulins from human serum through affinity monolith chromatography. Affinity‐based monolithic columns with immobilized protein A, G, or L were used for antibody isolation. Monolithic stationary phases have a high surface accessibility of binding sites, large flow‐through channels, and can be operated at high flow rates, making them the ideal supports for HTP isolation of biopolymers. The presented method can be used for HTP screening of human serum in order to simultaneously isolate all three above‐mentioned immunoglobulins and determine their concentration and changes in their glycosylation pattern as potential prognostic and diagnostic disease biomarkers.