We developed and evaluated a model for predicting the flow packing of nonrigid chromatographic resins. The model is based on elasticity theory and accounts for resin rigidity And column diameter. When a modulus determined from a standard mechanical compression (consolidation) test is used, the model captures the primary phenomena of the scale-up process. However, moduli determined from flow-packing experiments improve the accuracy of the predictions and show that the apparent rigidity of chromatographic resins is lower for flow packing than for mechanical compression. Using a modulus from flow-packing experiments provided quantitative scale-up predictions of flow packing carried out in columns with diameters between 200 and 450 mm at different locations and by different operators.