The aim of the research is to study the effect of the position of the opening on the ultimate load capacity of the orthogonal solid slab. A yield line theory is used for the prediction of the ultimate load capacity of an orthogonal concrete slab with and without rectangular corner opening subjected to uniformly distributed load (UDL). In this study, two locations of the opening are considered: the rectangular opening provided at the corner and the interior corner of the slab. All possible governing, geometrically admissible, collapse mechanisms were identified, virtual work equations were derived, and to solve the equations a computer program has been developed. The same aspect ratios of the slab and the opening, and opening sizes up to 0.4 times the slab length the were considered. Four boundary conditions of the slab with different opening sizes are considered to present the design charts for affine coefficients.