A finite element analysis and design of austenitic and duplex stainless steel tubular section beam-columns is presented in this paper. The nonlinear finite element model was verified against experimental results of stainless steel tubular section beam-columns and beams. In this study, square and rectangular hollow sections were investigated. It was shown that the finite element model closely predicted the ultimate loads and failure modes of the tested beam-columns and beams. Hence, the finite element model was used for an extensive parametric study. The axial compressive strengths of the beam-column specimens predicted by the finite element analysis are compared with the design strengths calculated using the linear interaction equation and direct strength method. Reliability analysis was performed to assess the reliability of these design rules. It is shown that these design rules generally provide accurate and reliable predictions for stainless steel tubular section beam-columns. Design recommendations for linear interaction equation and the direct strength methods are proposed for stainless steel SHS and RHS beam-columns.