Background: Women are underrepresented in sacubitril/valsartan (SV) clinical trials. The aim of this study was to assess sex-specific differences in efficacy, tolerability, and safety of SV in real-world heart failure with reduced ejection fraction (HFrEF) patients. Methods: A prospective registry in 10 centers including all patients who started SV during the last 6 months was analyzed in this study. Results: A total of 427 patients were included, 126 (29.5%) were women. There were no substantial differences in HFrEF treatment before SV initiation, although fewer women than men carried an implantable cardioverter defibrillator (57 [45.2%] vs. 173 [58.1%], p = 0.02). SV starting dose was 24/26 mg b.i.d. in 206 patients (48.2%), 49/51 mg b.i.d. in 184 (43.1%), and 97/103 mg b.i.d. in 34 (8.2%), without relevant differences associated to sex. There were no losses during a mean follow-up of 7.0 ± 0.1 months. The proportion of patients who discontinued the drug (16 [12.7%] women vs. 33 [11.0%] men, p = 0.66) or presented SV-related adverse effects (31 [24.6%] women vs. 79 [26.5%] men, p = 0.72) was also similar in both sexes. However, female sex was an independent predictor of functional class improvement in the multivariate analysis (odds ratio 2.33, 95% confidence interval: 1.24–4.38, p = 0.04). Conclusions: SV in women with HFrEF has a similar tolerability as in men. Females seem to have a more frequent functional class improvement than males.