OBJECTIVES: Economic evaluations of BIAsp have been published in the context of different countries. This study aimed to evaluate the financial impact from a perspective of patients treated by public providers of different adoption rates of Biphasic Insulin Aspart (BIAsp; NovoMix 30 FlexPen®) versus Biphasic Human Insulin (BHI; Mixtard Penfill®) in treating T2DM. METHODS: An Excel based 5-year budget impact model was built to estimate insulin treated patients by public providers using the local prevalence data. The published demographic, efficacy and adverse event data for ASEAN subgroup analyses of Achieve study was applied. Both insulin acquisition costs and medical costs for major hypoglycaemia and other complications were applied with a 3% discount rate to the estimated corresponding incidence rates derived from the UKPDS equations. The projected adoption rates were based on the 2013 utilisation volume data.  Other local specific considerations e.g. subsidized selling prices and co-payments were included in the analyses for an assumed size of eligible patients. Sensitivity analyses were conducted. RESULTS: The adoption rates of BIAsp were assumed to increase from 23.6% in 2013 to 30% or 36.5% in 2018 for base case and upside scenario, respectively.   In comparison to base case scenario, increases in adoption rate of BIAsp were associated with a cumulative increase up to slightly greater than S$ 2.02M in insulin acquisition cost but a potential cumulative net saving up to approximately S$0.92M in overall total costs over 5 years, attributing to subsidized selling price of BIAsp assuming it is included standard drug list and its significantly lower major hypoglycaemia risk, respectively. Cost savings were predicted for other complications. CONCLUSIONS: The wider adoption of BIAsp was predicted to result in net cost savings from patient perspective in Singapore.  More cost saving would be estimated in analyses with reduced productivity loss from a societal perspective.