This paper presents a method for the selection of candidates for shading and blocking in central receiver systems (CRS). The main advantage of this algorithm is that it produces a reduced list of candidates with no upper limit on the total number, and it selects only those heliostats which produce real shading or blocking, eliminating redundant candidates. The objective is to contribute to a reduction in the execution times of the shading and blocking efficiency calculation in CRS, without a significant drop in accuracy. The method consists of three filtering levels, which progressively reduce the number of candidates, and it is specifically designed for use in performance simulation and optimisation applications for CRS. Its performance in this context has been compared with that of other selection algorithms, in terms of the number of selected candidates for each method and the execution times for determining the annual shading and blocking efficiency. The results indicate that the proposed method reduces the list of selected candidates to nearly 23% of those selected by other methods (spheres method) and up to 22% the execution times without affecting the numerical efficiency results. (c) 2020 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).