Aims. Isolated greater tuberosity fractures make up 17–21% of proximal humeral fractures, 30% are associated with shoulder dislocation. Conservative management of minimally displaced fractures (<5 mm) is recommended. There are few guides to which and how many fractures displace over time. Methods. A retrospective analysis of isolated greater tuberosity fractures presenting to a shoulder fracture clinic over 1 year was performed. Patients were identified from shoulder fracture clinic lists and a bluespier database. Radiological fracture displacement was measured from the edge of the defect in the humeral head to the closest edge of the greater tuberosity. All measurements were performed by three oberservers on two occasions. Data was analysed to study the relationship between initial displacement and fracture stability and between concurrent dislocation and fracture stability. Inter-observer analysis was performed. Results. 64 (m:32; f:32; mean age 53) patients were identified. 37 were displaced 0–5 mm at presentation, 18 were displaced 5–10 mm, 9 were displaced >10 mm. Of those displaced less than 5 mm on presentation, 22% (n8) further displaced to greater than 5 mm and 5% (n2) to >10 mm at follow-up. Of those displaced 5–10 mm on presentation, 17% (n3) displaced to >10 mm. 42% (n27) of fractures were associated with dislocation; they had greater displacement at presentation. In the 0–5 mm displacement group that displaced >5 mm, 88% (n7) had concurrent dislocation. Inter-observer analysis of the x-ray measurement showed moderate agreement (0.684). Conclusion. Isolated greater tuberosity fractures displaced less than 5 mm at presentation and that are not associated with dislocation are stable. Concurrent dislocation is associated with both greater fracture displacement at presentation and ongoing fracture instability