With the increasing popularity of online queuing systems, it remains controvertial whether higher information transparency increases customers’ willingness to wait. Based on theories of uncertainty avoidance and time perception, two experiments were conducted to systematically examine the role of queuing information transparency on customers’ willingness to wait. The results showed that: (1) information transparency positively predicted customers’ willingness to wait. (2) Objective waiting time moderated the relationship between information transparency and willingness to wait. (3) Subjective time perception mediated the effect of information transparency on waiting willingness, and this mediation was further moderated by objective waiting time. Specifically, under short waits, high transparency increased willingness to wait; whereas under medium-to-long waits, high transparency reduced willingness to wait by increasing subjective time perception. These findings reveal the “double-edged sword” effect of information transparency and suggest a dynamic transparency strategy, providing practical implications for improving public service effectiveness and customer satisfaction.