Symmetrical steel moment frames that are subjected to sidesway forces due to unsymmetrical live loads will undergo sidesway. The P-delta effects on a moment frame under the influence of sidesway forces is studied. The effective length method is used for the second-order analysis specified in the American Institute Steel Construction - Load and Resistance Factor Design (AISC-LRFD). This study investigates the P-delta effects on a multi-story, multi-bay steel moment frame subjected to sidesway forces caused by various unsymmetrical live load patterns. The study focuses on the interaction of axial and bending moment in the columns. The actual response of a moment frame is estimated by amplifying the results of a first-order elastic analysis using moment magnification factors. The moment magnification factors for each story of the steel moment frame are summarized.