The effect of temperature on survival, oviposition, gonotrophic development and a life-history factor of vectorial capacity were examined in adult Culicoides sonorensis (Wirth & Jones) that originated from two geographic locations. Flies originating from the US (Colorado) had slightly reduced survival following a blood meal compared with wild flies collected in southern Alberta (AB). Survival of AB flies declined in a curvilinear fashion with temperature while survival of US flies showed a linear response to temperature. The survivorship curve of the AB flies more closely followed a Weibull distribution than an exponential, indicating survival was age-dependent. Survivorship of the US flies followed an exponential distribution. Females from both sources laid similar numbers of eggs throughout their life. The first eggs were laid by females from both sources at 31.9 DD9.3. Dissections of blood-fed flies reared at various temperatures indicated that flies from both sources were 90% gravid at 32 DD9.3. Relationships among temperature and life-history components of vectorial capacity were similar among flies from the two sources and indicated that vectorial capacity would be ca. 1.8 – 2.6 –fold greater in a southern US climate compared with south-western Canada due solely to the effects of temperature on the life-history C. sonorensis. Using life-history estimates derived from Weibull model had little effect on estimating vectorial capacity, while using estimates derived from the exponential model slightly overestimated vectorial capacity.