AimsTo evaluate the clinical features and impact of flash glucose monitoring in older adults with type 1 diabetes (T1D) across age groups defined as young‐old, middle‐old, and old‐old.Materials and MethodsClinicians were invited to submit anonymized intermittently scanned continuous glucose monitoring (isCGM) user data to a secure web‐based tool within the National Health Service secure network. We collected baseline data before isCGM initiation, such as demographics, glycated haemoglobin (HbA1c) values from the previous 12 months, Gold scores and Diabetes Distress Scale (DDS2) scores. For analysis, people with diabetes were classified as young‐old (65–75 years), middle‐old (>75–85 years) and old‐old (>85 years). We compared baseline clinical characteristics across the age categories using a t test. All the analyses were performed in R 4.1.2.ResultsThe study involved 1171 people with diabetes in the young‐old group, 374 in the middle‐old group, and 47 in the old‐old group. There were no significant differences in baseline HbA1c and DDS2 scores among the young‐old, middle‐old, and old‐old age groups. However, Gold score increased with age (3.20 [±1.91] in the young‐old vs. 3.46 [±1.94] in the middle‐old vs. 4.05 [±2.28] in the old‐old group; p < 0.0001). This study showed reduced uptake of insulin pumps (p = 0.005) and structured education (Dose Adjustment For Normal Eating [DAFNE] course; p = 0.007) in the middle‐old and old‐old populations compared to the young‐old population with T1D. With median isCGM use of 7 months, there was a significant improvement in HbA1c in the young‐old (p < 0.001) and old‐old groups, but not in the middle‐old group. Diabetes‐related distress score (measured by the DDS2) improved in all three age groups (p < 0.001) and Gold score improved (p < 0.001) in the young‐old and old‐old populations but not in the middle‐old population. There was also a significant improvement in resource utilization across the three age categories following the use of is CGM.ConclusionThis study demonstrated significant differences in hypoglycaemia awareness and insulin pump use across the older age groups of adults with T1D. The implementation of isCGM demonstrated significant improvements in HbA1c, diabetes‐related distress, hypoglycaemia unawareness, and resource utilization in older adults with T1D.