Entomopathogenic nematodes (EPN) such as Steinernema spp. and Heterorhabditis spp. are obligate parasites of insects and effective biocontrol agents. Infective juveniles (IJs) of Steinernema carpocapsae and Heterorhabditis megidis are distantly related and exhibit different foraging behaviours but utilise similar volatiles to find hosts. These IJs live in the soil year-round and are exposed to a range of temperatures and associated stressors. Here we attempt to understand how exposure to low temperatures, and the duration of this exposure, affects the behaviour and stress resistance of these IJs. S. carpocapsae and H. megidis have similar responses to many odorants upon emergence from their natal host. The chemotaxis of H. megidis at 20°C is generally enhanced after exposure to lower temperatures, whereas the chemotaxis of S. carpocapsae at 20°C tends to be inverted by exposure low temperatures. Exposure to temperatures below culture temperature affects the chemotaxis of H. megidis gradually, whereas S. carpocapsae behave in a binary manner. Brief exposure to 9°C causes the behaviour of S. carpocapsae IJs to be altered and increased their resistance to freezing and desiccation for weeks afterwards. Label free quantitative proteomics confirms that exposure to 9°C for 1 week elicits dramatic increases in chaperone proteins in S. carpocapsae IJs, which are retained at high levels for 2 weeks after their transfer to 20°C. The proteome of S. carpocapsae IJs exposed to 9°C for 1 week and subsequently transferred to 20°C for 2 weeks conforms closely to that of IJs kept at 9°C for 3 weeks. Thus, S. carpocapsae IJs display a high degree of plasticity, and their behaviour and stress resistance may be manipulated by brief controlled exposure to low temperatures.