To investigate potential water-source microbes, 44 samples of water offered to individually caged psittacine birds were aseptically collected from 14 bird-owning households and evaluated for the presence of coliforms, Escherichia coli, heterotrophic bacteria, and Pseudomonas aeruginosa. No samples were positive for E coli; however, 21 of 25 water samples (84%) from open containers and 7 of 19 samples (37%) from bottles exceeded US Environmental Protection Agency standards for coliforms. Fourteen of 24 open containers (58%) and 7 of 19 bottles (37%) grew heterotrophic bacteria that exceeded 500 colonies/ml. Pseudomonas aeruginosa was isolated from water samples from 1 open container and 1 bottle. These results suggest that potentially pathogenic bacteria can be found in water offered to companion psittacine birds. Additional studies are needed to assess whether these bacteria are clinically important causes of disease and to develop husbandry methods that will reduce contamination.