This paper deals with pricing of reactive power in power systems. In general, reactive power responds to a small share of the total market power. As a consequence, not much attention has been paid for this issue. The problem becomes more challenging if the system security issue is addressed considering reactive power market as an auxiliary tool to enhance the voltage level proﬁle and the reactive power control to obtain a larger load margin. For this sake, for each transaction executed, the responsibility of the reactive power changes is determined, as well as some control actions to reduce the system loss in the critical area, so the load margin is increased. Pricing these control actions is then discussed under a novel approach proposed in the paper, followed by a discussion about some system conﬁgurations and operating conditions. The tests are executed with the help of a sample real system with 39 buses with all limits considered, so the results may be replicated.