There is strong evidence for a positive relationship between geographic range size, body size and relative abundance in terrestrial systems, so much so it is considered an ecological “norm.” However, in marine fishes the evidence for this relationship is weak and in freshwater fish it is equivocal. If such patterns exist, they can be used to identify species at risk of extinction. Using existing information from databases and the literature, and accounting for phylogenetic signatures, we analysed the relationship between range-size, body-size and abundance in 263 species of Australian freshwater fish. We tested if these three factors relate to diadromy, latitude, longitude, endemism at the regional and national level and conservation status. Range size and body size were strongly positively correlated. Species listed as threatened under the Federal Government’s EPBC Act had a range size an order of magnitude smaller than unlisted species for a given body size. Relationships with abundance were weakly negative, with no effect of conservation listing. Thus, geographic range size may be a good indicator of potential extinction risk, whereas abundance is less reliable. This study suggests that many species may be at risk of extinction and require conservation listing. Further, the macro-ecology of Australian freshwater fish is distinct from freshwater fishes in North America and Europe, likely due to the relatively stable nature of the Australian environment and the absence of large-scale glaciations.