To analyse antibiotic prescribing behaviour in English primary care with particular regard to which antibiotics are prescribed and for which conditions. Primary care data from 2013-15 recorded in The Health Improvement Network (THIN) database were analysed. Records with a prescription for systemic antibiotics were extracted and linked to co-occurring diagnostic codes, which were used to attribute prescriptions to clinical conditions. We further assessed which antibiotic classes were prescribed and which conditions resulted in the greatest share of prescribing. The prescribing rate varied considerably among participating practices, with a median of 626 prescriptions/1000 patients (IQR 543-699). In total, 69% of antibiotic prescriptions (n = ...