We wished to compare the acuity of adults vs. children using a representative sample drawn from a geographically isolated region. We retrospectively analyzed Emergency Department (ED) patient logs, billing records, and trauma data from two hospitals serving a geographically isolated region (Santa Barbara, California), and compared the following measures of acuity by age, triage category, rates of admission, billing levels of service, procedures (ED intubation, cardiopulmonary resuscitation, and invasive line placement), and trauma team activations. We analyzed 88,864 patients treated at the two EDs over an 18-month period, of whom 15,589 (17.5%) were children (< 18 years of age). Adults were 1.93 times more likely than children to receive the highest triage category (95% confidence interval [CI] 1.65-2.27), 3.47 times more likely to be admitted (95% CI 3.26-3.70), 2.92 times more likely to receive critical care or extended examination billing (95% CI 2.78-3.06), 2.63 times more likely to be intubated (95% CI 1.78-3.88), 4.59 times more likely to receive cardiopulmonary resuscitation (95% CI 1.67-12.57), and 4.39 times more likely to receive invasive line placement (95% CI 1.93-10.01). No age-based differences were noted in the rates of highest-level trauma team activation or admission directly to the operating room. ED children have overall lower acuity than ED adults-by many measures, several-fold less. These findings may have important implications for ongoing skills retention and proficiency in critical care for practitioners whose ED practice is restricted to representative samples of children.