This paper presents a heuristic approach for optimal feeder reconfiguration of radial distribution systems (RDS). Optimal feeder reconfiguration involves the selection of the best set of branches to be opened by considering the all tie switches, such that the resulting RDS has the desired performance. Amongst the several performance criteria considered for optimal feeder reconfiguration, line maximizing loadability is an important one. In this paper an algorithm is proposed based on simple heuristic rules and identified an effective switch status configuration of distribution system for maximizing the line maximum loadability of the system. The line maximum loadability, power loss and voltage profile calculation of the best switching combination are found by load flow solution. Compared to other published articles, the proposed method reduces the switching combinations searched and gives the optimum solution in few number of load flow runs. To demonstrate the validity of the proposed algorithm, computer simulations are carried out on 33-bus system and the performance of the proposed method compared with the other existing methods.