Little is known about the characteristics and treatments of patients with severe asthma across Europe but both are likely to vary. This is the first study in the ERS Severe Heterogeneous Asthma Research collaboration, Patient-centred (SHARP) and it is designed to explore these variations. Therefore, we aimed to compare characteristics of patients in European severe asthma registries and treatments before starting biologicals. This was a cross-sectional retrospective analysis of aggregated data from 11 national severe asthma registries that joined SHARP with established patient databases. Analysis of data from 3,233 patients showed many differences in characteristics and life style factors. Current smokers ranged from 0% (Poland, PL, Sweden, SE) to 9.5% (Belgium, BE), mean BMI ranged from 26.2 (Italy) to 30.6 kg/m2 (UK) and the largest difference in mean pre-bronchodilator FEV1% pred. was 20.9% (Netherlands vs Hungary). Before starting biologicals patients were treated differently between countries: mean ICS dose ranged from 700-1335 μg/day between those from Slovenia (SL) vs PL when starting anti-IL-5 antibody and from 772-1344 μg/day in those starting anti-IgE (SL vs Spain). Maintenance OCS use ranged from 21.0% (BE) – 63.0% (SE) and from 9.1% (Denmark) to 56.1% (UK) in patients starting anti-IL-5 and anti-IgE, respectively. The severe asthmatic population in Europe is heterogeneous and differs in both clinical characteristics and treatment, often appearing not to comply with the current ERS/ATS guidelines definition of severe asthma. Treatment regimens before starting biologicals were different from inclusion criteria in clinical trials and varied between countries.