In this paper, we investigate the analysis of reachability and controllability for time‐varying linear systems evolving on nonuniform time domains also known as arbitrary time scales. Based on appropriate operators, some necessary and sufficient conditions are derived to guarantee the reachability for this class of systems using linear algebra tools. Furthermore, a link between optimality and the proposed operators is given. Then, the connection between reachability and controllability analysis on arbitrary time scales is discussed. Through the paper, some examples illustrate the theoretical results.