This study examines the global distribution patterns and factors influencing the establishment of non-native freshwater fish species. Using a comprehensive database of 14,953 freshwater fish species across 3119 river basins, the authors identify global hotspots for exotic and translocated non-native fishes. The findings show that both types of non-native fishes are more likely to occur when closely related to native fishes, regardless of measures of phylogenetic relatedness, biogeographical realms, and highly invaded countries. This contradicts Darwin's naturalization hypothesis, suggesting that the presence of close relatives indicates suitable habitats rather than intensified competition. The study provides insights into the global patterns of non-native freshwater fish species and their phylogenetic correlates, laying the groundwork for understanding and predicting future fish invasions in freshwater ecosystems. The results highlight the importance of considering phylogenetic relatedness in assessing the ecological and economic impacts of non-native fish species and inform management strategies to address these invasions.This study examines the global distribution patterns and factors influencing the establishment of non-native freshwater fish species. Using a comprehensive database of 14,953 freshwater fish species across 3119 river basins, the authors identify global hotspots for exotic and translocated non-native fishes. The findings show that both types of non-native fishes are more likely to occur when closely related to native fishes, regardless of measures of phylogenetic relatedness, biogeographical realms, and highly invaded countries. This contradicts Darwin's naturalization hypothesis, suggesting that the presence of close relatives indicates suitable habitats rather than intensified competition. The study provides insights into the global patterns of non-native freshwater fish species and their phylogenetic correlates, laying the groundwork for understanding and predicting future fish invasions in freshwater ecosystems. The results highlight the importance of considering phylogenetic relatedness in assessing the ecological and economic impacts of non-native fish species and inform management strategies to address these invasions.