Abstract OBJECTIVES The present study sought to develop a reliable calcium score (Ca-score) to predict paravalvular leak (PVL) in patients undergoing transcatheter aortic valve (AV) implantation. METHODS A total of 965 patients were prospectively included from 2012 to 2019. Preprocedural contrast-media-enhanced computed tomography scans were analysed regarding the amount of AV cusp calcification and the presence of upper and lower left ventricular outflow tract calcification. The calcium volume threshold of each AV cusp [non-coronary cusp (NCC); left coronary cusp (LCC); right coronary cusp (RCC)] with optimal PVL prediction was defined using the Youden index value derived from receiver operating characteristic analysis. The final score was developed based on the multivariable regression analysis, while individual variables were weighted based on their corresponding odds ratio. RESULTS The AV calcium volume threshold with optimal PVL prediction was 733.6, 296.0 and 131.2 mm3 for the NCC, RCC and LCC respectively. Overall, calcification of the upper left ventricular outflow tract was present in 233 (23%), 111 (12%) and 304 (32%) of patients below the NCC, RCC and LCC respectively, while 260 (27%), 44 (5%) and 217 (23%) patients suffered from calcification under the NCC, RCC and LCC, respectively. A total Ca-score of ≥4 was present in 356 (37%) of patients and was independently associated with ≥ mild PVL [odds ratio 3.662; 95% confidence interval (2.740–4.911); P < 0.001]. The area under the curve of the Ca-score was 0.713 [95% confidence interval (0.678–0.748); P < 0.001]. CONCLUSION The provided Ca-score independently correlates with the development of PVL and improves risk stratification in patients undergoing transcatheter AV implantation.