Extended surfaces find numerous applications in heat transfer devices for a decade. So, understanding the underlying flow physics and heat transfer distribution is the prime importance of the present work. The present study investigates the effects of the different arrangements of rectangular ribs in a three-dimensional heated channel with the prime objective to augment heat transfer. Numerical simulations of turbulent forced convection are carried out by introducing twelve different ribbed configurations at the lower wall of the channel. Constant heat flux is supplied on the lower wall while the upper wall is insulated. The computations were carried out using a realizable k − ε model in RANS formulation implemented in finite volume-based solver ANSYS ICEPACK 19.2®. Assessment of the coefficient of heat transfer and frictional losses are systematically evaluated for the different rib arrangement test cases. A novel offset staggered rib arrangement is proposed which delivers a significantly higher magnitude of heat transfer augmentation compared to conventional uniformly spaced ribs. Detailed investigation shows the inability of evenly spaced rectangular ribs in attaining high heat transfer enhancement in row-wise arrangements, which is used in most of the published literature to date. The underlying flow physics behind the enhancement of thermal transport in different configurations is further investigated in more detail. The present work provides a detailed preliminary investigation of the arrangement of ribs that can be used in designing practical thermal devices.