Emergency hospital admissions for respiratory diseases are sharply reduced by 18% on Christmas Day compared with the admissions on previous days, according to a single report based on data from the Office of National Statistics in England. Respiratory admissions and respiratory deaths increase above the trend on the next and subsequent days. We hypothesized that intensive care unit (ICU) admissions from the emergency department (ED) decrease during holidays and increase immediately after. We retrospectively reviewed the electronic medical records of ICU admissions from the ED during, before, and after major holidays at the University of Minnesota Medical Center (UMMC) and Fairview Health System. In Fairview Health System, the average number of ED ICU admissions per day was 3.6 ± 2 (SD) and was not different between the various periods (analysis of variance, P = 0.77). In UMMC, the average number of ICU admissions per day directly from the ED was 0.7 ± 0.8 (SD) and was also not different between the various periods (analysis of variance, P = 0.82). Similarly, in Fairview Health System the average number of ED ICU admissions per day during office hours (regular weekdays) was not different compared with the average number of admissions during off-hours (weekends and holidays) (t test, P = 0.88). In UMMC, the number of ED ICU admissions per day did not vary between office hours (regular weekdays) and weekends-holidays (t test, P = 0.99). ICU workload variation between office hours and off-hours is solely related to referrals and transfers from other facilities and other hospital units except the ED.