OBJECTIVES: Accuracy standards of blood glucose monitoring systems have been recently revised. The revised standard, ISO 15197:2013, tightens the range of results considered accurate from a 20% deviation from the reference value to a 15%.  The objective of this analysis is to evaluate the economic value of accuracy differences between ISO compliant and non ISO compliant meters in Spain, using a modelling approach. METHODS: Clinical and economic outcomes were simulated over a 20-years time horizon by means of a Markov model. 4 health states were considered, including no event, non-fatal hypoglycemia, fatal hypoglycemia and death due to other causes.  Model inputs were derived from published sources.  Inputs included Spanish Type 2 diabetes mellitus (T2DM) insulin-treated population size, risk of severe hypoglycemic event (SHE) due to meter error, cost per SHE and rates of death due to SHE and other causes. RESULTS: A reduction of the inaccuracy range from 20% to 15% would translate into a 25.5% reduction of SHE. The incremental cost per SHE avoided would be -2,795€. The reduction in SHE would lead to cost savings of 135€ per T2DM insulin-treated patient and year. Considering there are 379,728 T2DM insulin-treated patients in Spain, the total cost savings would exceed 51€ million, meaning 0.9% of total Spanish diabetes expenditure and 0.07% of total Spanish health care expenditure. CONCLUSIONS: Self-monitoring blood glucose is a key component of diabetes management as it is often used in clinical decision making. It is therefore critical that these devices are accurate and precise. The results of this study might encourage the conversion of all patients using non ISO compliant meters to ISO compliant meters in the European Union, where ISO 15197:2013 will become mandatory in May 2016. It might also enhance stricter standards in countries where these requirements will not be mandatory.