Whether gill area constrains fish metabolism through oxygen limitation is a debated topic. Here, we provide insights into this question by analyzing mass-specific metabolic rates across 44 teleost fishes extracted from FishBase. We explore whether species deviations from metabolic rates predicted by body mass can be explained by species gill area. We show that the gill area explains ~26-28% of species-level deviations from mass-specific metabolic rates. Our findings suggest that gill area might indeed be one of the factors limiting metabolic rate in fishes.