BACKGROUND: The aim of this study was to analyse rates of antibiotic usage in chronic rhinosinusitis (CRS) in primary care in England and Wales and to identify trends in the choice of antibiotics prescribed. METHODS: We used linked data from primary care EHRs, with diagnoses coded using the Read terminology (Clinical Practice Research Datalink) from consenting general practices, with (2) hospital care administrative records (Hospital Episode Statistics, HES recorded using ICD-10). RESULTS: From the total of 88,317 cases of CRS identified, 40,462 (46%) had an antibiotic prescription within 5 days of their first CRS diagnosis. Of patients receiving a first line antibiotic within 5 days of CRS diagnosis, over 80%, in each CRS group, received a subsequent prescription for an antibiotic. Within 5 years of diagnosis, 9% are estimated to have had 5 or more antibiotics within 5 days of a CRS-related consultation. With data spanning almost 20 years, it was possible to discern trends in antibiotics prescriptions, with a clear increasing trend towards macrolide and tetracycline prescribing evident. CONCLUSIONS: While antibiotics may have been prescribed for acute exacerbations, we have found high rates of repeated antibiotic prescription in some patients with CRS in primary care. There is a need for stronger evidence on the role of antibiotics in CRS management.