© Canadian Association of Emergency Physicians. Introduction: The objective of this study was to compare the emergency department (ED) management and rate of admission of acute decompensated heart failure (ADHF) between two hospitals in Canada and the United States and to compare the outcomes of these patients. Methods: This was a health records review of adults presenting with ADHF to two EDs in Canada and the United States between January 1 and April 30, 2010. Outcome measures were admission to the hospital, myocardial infarction (MI), and death or relapse rates to the ED. Data were analysed using descriptive, univariate and multivariate analyses. Results: In total, 394 cases were reviewed and 73 were excluded. Comparing 156 Canadian to 165 U.S. patients, respectively, mean age was 76.0 and 75.8 years; male sex was 54.5% and 52.1%. Canadian and U.S. ED treatments were noninvasive ventilation 7.7% v. 12.8% (p = 0.13); IV diuretics 77.6% v. 36.0% (p<0.001); IV nitrates 4.5% v. 6.7% (p = 0.39). There were significant differences in rate of admission (50.6% v. 95.2%, p<0.001) and length of stay in ED (6.7 v. 3.0 hours, p<0.001). Proportion of Canadian and U.S. patients who died within 30 days of the ED visit was 5.1% v. 9.7% (p = 0.12); relapsed to the ED within 30 days was 20.8% v. 17.5% (p = 0.5); and had MI within 30 days was 2.0% v. 1.9% (p = 1.0). Conclusions: The U.S. and Canadian centres saw ADHF patients with similar characteristics. Although the U.S. site had almost double the admission rate, the outcomes were similar between the sites, which question the necessity of routine admission for patients with ADHF.