The suitability for laboratory culture and comparative sensitivity of three species of New Zealand freshwater copepod (Calamoecia lucasi Brady, Boeckella delicata Percival, and Mesocyclops cf. leuckarti Claus) to pentachlorophenol (PCP) was assessed. Acute bioassays used two life stages (nauplii and adults). Acute 48‐h lethality tests were conducted at 22°C with laboratorycultured animals of all species and at varying temperatures with seasonally collected C. lucasi adults. Mean 48‐h median lethal concentration values for nauplii ranged from 52 to 227 μg/L PCP for C. lucasi and B. delicata, respectively, and from 106 to 173 μg/L for adult C. lucasi and M. leuckarti, respectively. The survival rate in controls was ≥95% in acute tests, with the exception of C. lucasi nauplii, in which it was 60%. Mean 48‐h median lethal concentration values for seasonally collected C. lucasi adults were significantly higher in summer than in all other seasons. Chronic sublethal tests starting with nauplii <24 h old measured time to metamorphosis. Pentachlorophenol delayed metamorphosis in all species. Chronic toxicity values were 14, 61, and 104 μg/L PCP for C. lucasi, B. delicata, and M. leuckarti, respectively. The mortality rate in controls was also high in C. lucasi sublethal tests (65%), and of the three species, they were the most difficult to culture.