Underwater Acoustic Sensor Networks (UW-ASN) are provisioned with limited bandwidth, long variable propagation delay, limited available energy, highly unreliable acoustic channels, and random node mobility. Consequently, efficient data routing between source destination pair requires UW-ASN to apply a technology different than terrestrial networks. For the past few years researchers have proposed many robust and efficient routing protocols for UW-ASN, thus reviewing the challenges posed by stringent underwater environment. These protocols can be broadly categorized into localization based and localization-free protocols. This paper presents a critical review of beacon-based localization-free routing protocols and suggest possible solution to improve the working of studied beacon based protocols. This work categorizes beacon based protocols into hop-by-hop, end-to-end, single, and multiple parameters based forwarding protocols. This categorization will help to differentiate and identify the requirements for the development of new beacon-based protocols. Finally, this paper presents performance comparison based on simulation results and outlines the research gap and future directions. KEYWORDS energy consumption, link quality, sensor networks, underwater routing protocols Int J Commun Syst. 2017;30:e3375.wileyonlinelibrary.com/journal/dac