Stainless steel's characteristic nonlinear, rounded stress–strain behaviour requires accurate recognition in numerical modelling. Its response to cold-working is far more pronounced than that of ordinary carbon steel and hence appropriate modelling of the cold-worked corner regions is very important. Despite the importance of geometrical imperfections, their measurement is not a very common practice and assumed models are generally adopted in numerical investigations—often without proper verification. This paper investigates all important aspects for modelling stainless steel cross-sections through carefully designed parametric studies. Different cross-section types have been considered and the numerically obtained load–deformation responses have been compared with selected experimental results; the findings form the basis for specific guidelines. These proposals have been verified by application to all available stainless steel stub column tests obtained from different sources. The predicted numerical results have shown excellent agreement with those obtained experimentally.