This paper analyzes performance of cellular systems with shared resources, where the network with overlapping cells is modeled as a circuit switched network with direct routing. The influence of the degree of sharing, represented by cell overlap percentage, on the call blocking probability is investigated for three scenarios, including cells with proportional offered traffic and resources, cells dimensioned according to fixed blocking probability, and fixed improvement function. The numerical results show that by sharing the resources between the operators, the overall system efficiency can be improved. However, we identify the benefit of individual operators and show that it’s not equal but highly depends on the initial network dimensioning. Furthermore, we demonstrate that under specific conditions the blocking probability in an area is lower than for fully accessible system and therefore, sharing agreements may be more beneficial for some operators.