OBJECTIVES: Technological developments allow remote monitoring of patients and improve diabetes care. A mobile phone telemonitoring system (TM) might improve the ability of DM patients to engage in treatment. The objective is to estimate the annual costs that implementing a TM for glycaemic control in DM patients might represent to the National Health System and to society in Spain. METHODS: First, a systematic review of the literature was conducted to determine cost drivers in DM TM. Electronic databases were searched to identify national and international clinical and economic articles, published between January, 2001 and December, 2011, reporting on the clinical benefits, health resources used and costs associated to DM TM. Second, based on the data gathered, and adapted for Spain, and on the assumption that TM favors treatment compliance, a mathematical model was applied to determine the variation in costs associated to macro and micro DM complications risk reduction derived from hypothetically reaching 100% DM treatment compliance in groups of patients: compliant, noncompliant  and complications are undiagnosed. RESULTS: A total of 3.539 articles were identified; 48 were reviewed. TM decreases emergency visits (83%), disease related hospital admissions (75%), length of hospital admission (51%), visits to the outpatient clinic (40%) and to the specialist (19%). Reduction of indirect costs reaches 120.82 € per DM patient/year due to less travel expenses (-6.30 €/visits) and productivity gain (-54 €/visits). Assuming that 100% of uncompliant DM patients become compliant (n = 1,550,634 patients) costs associated to macro- and micro-vascular complications decreases by 5,500 € (€, 2011) million per year. Higher cost reductions are obtained in the most prevalent vascular complications. CONCLUSIONS: These preliminary results show that TM in DM patients reduces direct and indirect costs. Significant costs reduction can be reached if DM treatment compliance is improved with TM in Spain.