The aim of this study was to investigate if the flash glucose level monitoring system (FGM) is better than traditional self-monitoring of blood glucose level (SMBG) in helping patients in the outpatient clinic control their blood glucose and improve glycaemic control measured by the concentration of glycated haemoglobin (HbA1c).This was an observational real-life study based on data retrieved from a regional diabetes database and conducted in patients with Type 1 diabetes. HbA1c levels at baseline, and at six, nine and 12 months were compared in and between two groups counting 128 patients each. One group included patients who had recently started using the FGM system; the other patients who were using SMBG and otherwise following the routine protocol of the outpatient clinic.We found no difference between the FGM group and the SMBG group with respect to age, sex, weight, diabetes duration or HbA1c at baseline. After six months, HbA1c had been reduced from 64 to 60 mmol/mol (p = 0.00) in the FGM group, whereas it remained unchanged in the SMBG group (from 63 to 63 mmol/mol, p = 0.66). According to the ANOVA repeated measures test, HbA1c measures showed a significant trend of reduction from 65 to 60 mmol/mol (p = 0.002) over 12 months in the FGM group and no trend of reduction in the SMBG group (from 63 to 64 mmol/mol, p = 0.386) Conclusions: Changing the blood glucose measuring method from SMBG to FGM helped patients with Type 1 diabetes in an outpatient clinic reduce their HbA1c.none.not relevant.