Office work has a relative perception of safety for the worker. Data from surveillance schemes and population-based epidemiological studies suggest that office work carries a low risk of occupational asthma (OA). Office workers are frequently used as comparators in studies of occupational exposure and respiratory disease. We aimed to describe and illustrate our tertiary clinical experience of diagnosing OA in office workers. We searched the Birmingham NHS Occupational Lung Disease Service clinical database for cases of occupational respiratory disease diagnosed between 2002 and 2020, caused by office work or in office workers. For patients with OA, we gathered existing data on demographics, diagnostic tests including Occupational Asthma SYStem (OASYS) analysis of serial peak expiratory flow and specific inhalational challenge, and employment outcome. We summarised data and displayed them alongside illustrative cases. There were 47 cases of OA (5% of all asthma) confirmed using OASYS analysis of PEFs in the majority. Sixty percent of cases occurred in healthcare, education and government sectors. The most frequently implicated causative exposures or agents were: indoor air (9), printing, copying and laminating (7), cleaning chemicals (4), mould and damp (4), and acrylic flooring and adhesives (4). Exposures were grouped into internal office environment, office ventilation-related and adjacent environment. Clinicians should be vigilant for exposures associated with OA in office workers who present with work-related symptoms, where respiratory sensitizing agents may be present. A structured approach to assessment of the workplace is recommended.