The underwater acoustic sensor networks have drawn the attention of researchers around the globe because of its diversified applications. The network is based on battery-operated acoustic sensor nodes therefore, it is of utmost significance to design energy efficient routing proto-col. One of the major reasons for inefficient energy consumption is the imbalance utilization of energy in different areas of the underwater region which leads to hotspot issues. In this article, a novel localization-free Energy Efficient Clustering Routing Protocol based on Arithmetic Progression (EECRAP)is proposed. The underwater region logically segmented in to asymmetric layers based on arithmetic progression. The pro-posed solution is based on the residual energy, layer division, and depth division of the node which can mitigate the hotspot issue and balance energy utilization in the network. For energy preservation and network longevity, an innovative energy-efficient routing path selection is presented in which th esucceeding forwarder node is selected according to its residual energy, layer division, and the received signal strength. When compared with low-energy adaptive clustering hierarchy (LEACH), depth-based routing (DBR), energy efficient routing protocol based on layers and unequal clusters (EERBLCs), and energy efficient clustering multihop routing protocol (EECMR), the simulated results illustrate improvements in energy usage of 40.7%, 29%, 20.25%, and 11% overLEACH, EERBLC, DBR, and EECMR, respectively. Packet delivery ratio-wise, EECRAP is 58.44%, 55.77%, 49.87%, and7.61% dependable than DBR, LEACH, EERBLC, and EECMR, respectively. Dead nodes make EECRAP 68.7%, 23.1%, 8.7%,and 7.6% more efficient than LEACH, DBR, EERBLC, and EECMR, respectively.