With the intensifying competition in the electricity sales market, independent electricity sales companies, as new market entities, face the risks of “batch and zero upside down” and “bias assessment”. As the electricity sales service quality is unobservable beforehand, they also face the risk of information asymmetry. Therefore, optimizing their electricity sales strategy has important theoretical and practical significance. Independent power sales companies with different types of power sales service quality have different power purchase costs and deviation control capabilities, so the sales price and deviation assessment apportionment ratio (hereinafter referred to as apportionment ratio) can be an effective signal to convey the service quality of independent power sales companies. Considering the influence of the sales price and apportionment ratio on power users’ strategy choices, this paper establishes a singlesignal game model based on the apportionment ratio, a dualsignal game model, and the independent electricity sales company’s sales price strategy. Furthermore, it solves the Bayesian game model. Moreover, it compares the equilibrium results of different signal game, analyzes the conditions for achieving a separation equilibrium, and obtains the optimal strategy for an independent retail electricity company. The results show that, unlike the sales price signal, both the apportionment ratio signal and the dual signal can mitigate the risk of adverse selection in the electricity sales market. However, using the dual signal can help lower the optimal apportionment ratio and the sales price of the electricity sales company while increasing its electricity sales and profits. Moreover, the conditions for achieving a separation equilibrium are more relaxed. This research can provide decisionmaking support for regulating the operation of China’s electricity market and improving the efficiency of electricity market operation.