Abstract Aims To evaluate the association between chronic treatment with betablockers (BB) and the severity of decompensation and short-term outcomes of patients with acute heart failure (AHF). Methods and results We consecutively included all patients presenting with AHF to 45 Spanish emergency departments (ED) during six different time-periods between 2007 and 2018. Patients were stratified according to whether they were on chronic treatment with BB at the time of ED consultation. Those receiving BB were compared (adjusted odds ratio—OR—with 95% confidence interval—CI—) with those not receiving BB group in terms of in-hospital and 7-day all-cause mortality, need for hospitalization, and prolonged length of stay (≥7 days). Among the 17 923 recruited patients (median age: 80 years; 56% women), 7795 (43%) were on chronic treatment with BB. Based on the MEESSI-AHF risk score, those on BB were at lower risk. In-hospital mortality was observed in 1310 patients (7.4%), 7-day mortality in 765 (4.3%), need for hospitalization in 13 428 (75.0%), and prolonged length of stay (43.3%). After adjustment for confounding, those on chronic BB were at lower risk for in-hospital all-cause mortality (OR = 0.85, 95% CI = 0.79–0.92, P < 0.001); 7-day all-cause mortality (OR = 0.77, 95% CI = 0.70–0.85, P < 0.001); need for hospitalization (OR = 0.89, 95% CI = 0.85–0.94, P < 0.001); prolonged length of stay (OR = 0.90, 95% CI = 0.86–0.94, P < 0.001). A propensity matching approach yielded consistent findings. Conclusion In patients presenting to ED with AHF, those on BB had better short-term outcomes than those not receiving BB.