Pillar design in any underground metalliferous mine plays a crucial role in maintaining its overall stability and also preventing the underground structures from surface subsidence. Thus, the natural pillars, i.e., crown, rib and sill pillar left intact in the underground should be competent enough to withstand the induced stresses developed as a result of extraction as well as blasting, especially in large scale production methods. In addition to the crown pillars in adjacent levels, a barrier or surface crown pillar of sufficient thickness is also left intact between the ultimate pit bottom and the first level of extraction. This barrier crown pillar is of utmost importance as it is one of the deciding factors in determining the stability of the existing underground structures throughout the life of mine. The present study focuses on the stability of a 40 m barrier crown pillar existing below an open pit mine operating simultaneously with the underground mine. The targeted annual production of the underground mine is around 2.5 million tonnes. In this paper, a total of 107 finite element models of the underground mine have been analyzed considering elastic-constitutive material model. The simulation models are assessed in terms of vertical displacement and safety factor with variation in level interval, material properties, crown pillar thickness and sequence of stoping. Based on the results obtained from the numerical simulations, some useful conclusions have been drawn.