Abstract.1Individual supercooling points ranged from ‐2 to ‐44°C for six species of springtails, five species from the Swiss Alps and one from lowland Britain. Individuals ofIsotomurus alticola(Carl) andIsotoma viridisBourlet without gut contents had substantially lower supercooling points than those containing food material.2Juveniles were more cold resistant than adults in bothI.alticolaandIsotoma hiemalisSchött, both with respect to supercooling point and to their survival at prolonged subzero temperatures.3Temperature and acclimation time affected the degree of supercooling of four of the Alpine species especiallyI.hiemalis.4Duration of culture period had no consistent influence on the supercooling potential of all the species.5Tests for glycerol in the body fluids of the five Alpine springtails were negative, but the presence of a sugar, probably glucose, together with a five carbon polyhydric alcohol was indicated by chromatog