Survival after cold chilling and spring emergence of pea leafminer, Liriomyza huidobrensis (Blanchard), were evaluated in both the field and laboratory in 2001 and 2002. Spring emergence was evaluated through the use of traps placed in various fields and hoop-houses that had high populations of pea leafminers the previous season. No pea leafminer adults were captured in spring emergence cages during either year. To evaluate cold chilling in the laboratory, a factorial design with three temperatures (approximately −5, 0, and 5°C), eight exposure periods (0, 1, 2, 4, 8, 16, 32, and 64 d), and four replicates was employed. Pupal mortality increased as the length of exposure increased, with no survival after 64 d of chilling at any temperature. Chilling exposure periods in the laboratory were compared with the number of days per month that soil temperatures in the study area fell below 5, 0, and −5°C. No field-collected pupae exposed to winter field conditions survived until the spring. The pea leafminer seems to be unable to overwinter in southern Ontario, except in protected areas.