Outdoor temperature has direct and indirect impacts on public health, with extreme heat and extreme cold increasing mortality and causing illness. In this study, we investigated the effects of extreme cold and extreme heat on the number of emergency department (ED) care visits in Virginia between January 2015 and December 2023. The daily mean temperature in the patient home ZIP code was obtained and used to build statistical models that allow us to estimate the number of ED visits and pregnancy-related ED visits attributable to extreme temperatures up to 21 days after the day the temperature was experienced. We found that, in Virginia, there was a relationship between the number of ED visits and extremely high and extremely low temperatures. An excess number of ED visits and pregnancy-related ED visits was attributed to experiencing extreme heat and extreme cold, although the difference between the two extremes was less prominent for pregnancy-related visits.