Piles can contribute to the stability of soil slopes by adding resistive force against destabilizing forces of soil. The factor of safety (FSmp) against circular slip failure for soil slopes reinforced with piles is derived by incorporating the Morgenstern–Price method of slices using the limit equilibrium method. The present study uses plastic deformation theory and soil arching phenomenon between the piles interval to examine the factor of safety due to the influence of the pile row. The results obtained from the present study are compared with those obtained from the available studies. Studies have also been made regarding the influence of the pile parameters such as the diameter of the pile (D), location of the pile from the toe (Lx), the ratio of centre to centre distance between the piles to the diameter of a pile (D1/D) on FSmp. The influence of soil parameters including internal friction angle ( \(\phi\) ), slope angle ( \(\alpha\) ), and stability number ( \(c/\gamma H\) ) are also evaluated. The findings demonstrate that stabilization of slopes using piles increases the factor of safety considerably due to soil arching.