In this paper, the heat transfer equation is coupled to Navier–Stokes equations for a steady vertical channel. The objective of the present study is to investigate the electrically conducting viscous fluid with isothermal wall conductions with variable properties. The combined effects of temperature dependent thermal conductivity and temperature dependent viscosity are examined. The analysis is presented in dimensionless form and the resultant equations are obtained both analytically (Perturbation method) and numerically by fourth order R–K Fehlberg with shooting technique. The dimensionless parameters that influence the temperature field and the transverse velocity field are variable thermal conductivity parameter −0.5≤bk≤0.5, variable viscosity parameter −0.5≤bv≤0.5, applied electric field parameter E=−1,0,1, Hartman number 1≤M≤3, buoyancy parameter 0≤N≤1.5 and wall temperature ratio parameter −2≤m≤2.