Wireless sensor networks (WSNs) are commonly used for continuously monitoring applications. This paper investigates a base station assisted energy efficient routing for hierarchical clusters. The base station determines the number of clusters and the initial set of headset members. Moreover, instead of a single cluster head, a set of associates called a head-set manages the network clusters. The head-set approach not only optimizes energy consumption by reducing the number of elections but evenly distributes the long-range transmissions among the network nodes. Due to the controlled addition of redundant associates, the network is available for longer number of transmissions. The simulation results show that the proposed protocol outperforms the traditional clustering techniques.