In the present paper, we review the potential impacts of climate change on estuaries and fish utilising estuarine waters, with a focus on Australia. We investigate climatic and hydrological processes that may affect Australian estuaries, before discussing likely changes to their environmental features and entrance structures. Potential impacts on fish species and assemblages utilising estuaries are then discussed. We provide several case studies that illustrate some of the potential differences associated with different regions and types of estuaries, and acknowledge that climate is not the only variable likely to have an impact on these systems. We do not discuss potential climate impacts on offshore systems from estuarine material. For example, material exported from estuaries may subsidise coastal food webs (e.g. Connolly et al. 2009), and freshwater discharge from estuarine plumes may stimulate phytoplankton and subsequently zooplankton assemblages and fisheries offshore (e.g. Schlacher et al. 2008).