Design of columns requires accurate estimation of effective length factor (k-factor) and moment amplification factor. The former helps to understand the instability condition of the member and the latter to estimate the secondary moments. Advancement of computing technology made it easy to assess any structure for instability and incorporate the effects but current design codes still use very simplified, idealised methods for estimation of aforementioned quantities. Literature review suggests that there are three approaches for estimation of effective length factor namely, sub- assembly, storey buckling and system buckling. Most studies focused on improving the sub-assembly approach as it is the simplest and used by design codes. In the present study: (1) Characteristic expression of effective length factor is proposed considering the effects of flexure and shear deformations. The proposed expression is general in nature and can be used for any compression member, if the end rotational and translational restraints are available; the method is provided to estimate the end rotational and translational restraints from the linear elastic analysis of the whole frame. k factor charts are prepared for various lateral translational restraints and shear deformation factors. k factors of frames columns and structural walls are estimated by the proposed method and compared with those from the methods given in the design codes. (2) Analytical expression of moment amplification factor is derived considering the effects of end translational and shear restraint, primary moments, loading, shear deformation, axial load level. Proposed analytical expression of moment amplification factor is compared with empirical design code expressions. This study concludes that: (1) Design codes use simplified expressions and methods for estimating k factors and moment amplification factors, which do not reflect real frame conditions. The proposed method of estimating the k factor is general in nature and gives accurate results for partially braced frames. Also, shear deformation has significant influence on k-factor for shear dominated members especially in coupled wall frame system; and (2) Proposed moment amplification factor accounts various influencing parameters; axial load is identified as the most dominating parameter.