Purpose <p>Transdiagnostic symptoms are the subjective physical and mental features that span across various diseases and share commonalities irrespective of the diagnosis. This study investigated which transdiagnostic symptoms are reported in electronic health records of sick-listed employees and how these symptoms are described. Furthermore, differences in transdiagnostic symptoms were studied across diagnostic categories.</p> Methods <p>Cross-sectional register-based study of consultation notes recorded in electronic health records of 25,981 employees sick-listed due to mental, musculoskeletal, cardiovascular, neurological, or gastrointestinal disorders between April 2019 and March 2020. Electronic health records were randomly drawn until data saturation, defined as no new transdiagnostic symptoms in 10 consecutive electronic health records, resulting in a final analytic sample of 262 electronic health records. Descriptions of transdiagnostic symptoms were analysed in Atlas-ti using a thematic analysis.</p> Results <p>A total of 129 unique symptoms were identified in the 262 electronic health records and thematically categorised into seven groups: psychological symptoms, pain, fatigue, sleep symptoms, vegetative symptoms, cognitive symptoms, and physical symptoms. Psychological symptoms were most prevalent (36%), followed by pain (30%), and fatigue (25%). In the majority of the health records, sequences of transdiagnostic symptoms were reported with brief indications of cause, severity, duration and temporal course. Transdiagnostic symptoms varied across diagnostic categories, though pain was highly prevalent in all diagnostic categories.</p> Conclusion <p>Seven thematic groups of transdiagnostic symptoms were identified in electronic health records of sick-listed employees. These seven groups can be used in further studies to identify symptom profiles that are related to poor work outcomes.</p>