STUDY OBJECTIVE: We seek to determine whether patients living in areas affected by emergency department (ED) closure, with subsequent increased distance to the nearest ED, have a higher risk of inpatient death from time-sensitive conditions. METHODS: Using the California Office of Statewide Health and Planning Development database, we performed a nonconcurrent cohort study of hospital admissions in California between 1999 and 2009 for patients admitted for acute myocardial infarction, stroke, sepsis and asthma or chronic obstructive pulmonary disease. We used generalized linear mixed-effects models comparing adjusted inpatient mortality for patients experiencing increased distance to the nearest ED versus no change in distance. RESULTS: Of 785,385 patient admissions, 67,577 (8.6%) experienced an increase in distance to ED care because of an ED closure. The median change for patients experiencing an increase in distance to the nearest ED was only 0.8 miles, with a range of 0.1 to 33.4 miles. Patients with an increase did not have a significantly higher mortality (adjusted odds ratio 1.04; 95% confidence interval 0.99 to 1.09). In subgroups, we also observed no statistically significant differences in adjusted mortality among patients with acute myocardial infarction, stroke, asthma or chronic obstructive pulmonary disease, and sepsis. We did not observe any significant variations in mortality for time-sensitive conditions in sensitivity analyses that incorporated a lag effect of time after change in distance, allowance for a larger affected population, or removal of ST-segment elevation myocardial infarction from the acute myocardial infarction subgroup. CONCLUSION: In this large population-based sample, less than 10% of the patients experienced an increase in distance to the nearest ED, and of that group, the majority had less than a 1-mile increase. These small increased distances to the nearest ED were not associated with higher inpatient mortality among time-sensitive conditions.