Exposure to altered conductivity can negatively impact many freshwater system inhabitants, including bacteria, plants, invertebrates, and vertebrates. Several studies have shown increased conductivity to affect amphibian behavior and ecology. Comparatively fewer studies have taken a physiological approach to understanding the effects of altered conductivity in amphibians. This study used laboratory experiments to assess conductivity effects on stress hormone (corticosterone) levels in Jefferson Salamander (Ambystoma jeffersonianum), Wood Frog (Rana sylvatica), and Gray Treefrog (Hyla versicolor) larvae. Prey consumption (only in A. jeffersonianum) and survival (in all species) also was examined after exposure to increased conductivity (0, 2,000, 4,000, and 8,000 ppb). There was a significant positive effect of increased conductivity exposure on baseline corticosterone levels in A. jeffersonianum after 1-week exposure. Exposure to increased conductivity did not influence baseline corticosterone levels in R. sylvatica and H. versicolor or confinement-induced corticosterone levels in all three species. Prey consumption in A. jeffersonianum was significantly negatively associated with increased conductivity (4,000 and 8,000 ppb). No mortality occurred in any species as a result of exposure to increased conductivity. These results suggest that exposure to increased conductivity can be a powerful environmental stressor for amphibians, despite having species-specific effects on corticosterone levels.