Abstract Background The Comparison of Sacubitril–Valsartan versus Enalapril on Effect on NT-proBNP in Patients Stabilised from an Acute Heart Failure Episode (PIONEER-HF) trial demonstrated significant reductions in N-terminal pro-B-type natriuretic peptide. Our study explored the cost-effectiveness of the use of sacubitril-valsartan versus enalapril in acute decompensated heart failure from the Australian healthcare perspective. Methods A Markov model was designed using data from the PIONEER-HF trial to model the clinical progress and costs of patients over a lifetime time horizon. The model consisted of three health states: ‘alive and event-free’, ‘alive after non-fatal hospitalisation for acute decompensated heart failure’ or ‘dead’. Costs and utilities were estimated from published sources. The cost of sacubitril-valsartan (per the Australian pharmaceutical benefits schedule) was AU$7.08/day. Outcomes of interest were the incremental cost-effectiveness ratios in terms of cost per quality-adjusted life year gained and cost per year of life saved. Cost and benefits were discounted at 5.0% per annum. Results Compared to enalapril, sacubitril-valsartan was estimated to cost an additional AU$7464 (discounted) per person, but lead to 0.127 years of life saved (discounted) and 0.096 quality-adjusted life years gained (discounted) over a lifetime analysis. These equated to incremental cost-effectiveness ratios of AU$58,629/year of life saved (US$41,795, EU€58,629, GBP£32,001) and AU$77,889/quality-adjusted life year gained (US$55,526, EU€49,202, GBP£42,504). We have assumed a threshold of AU$50,000/quality-adjusted life year gained to suggest cost-effectiveness. Conclusions At its current acquisition price, sacubitril-valsartan in comparison to enalapril is not likely to be cost-effective in the management of acute decompensated heart failure in Australia. A price reduction of more than 25% would confer cost-effectiveness.