Trust is imperative for safe and effective human-automation relationships, especially in complex systems. Transparency, which is the communication of the automation’s behavior and intent to the operator, can be used to build trust in human-automation teams. The present study investigated the impact of transparency across the Human-Automation Teaming (HAT) lifecycle (pre-, during, and post-task) on human-automation trust, communication, and reliance. Participants engaged in a counter small-unmanned air systems simulation. They were randomly assigned to one of six conditions with different configurations of transparency (or lack thereof) across the lifecycle phases. Overall, we found modest outcomes for the influence of automation transparency across the HAT lifecycle on trust, situation awareness, workload, and task performance. While trust levels did not significantly differ across lifecycle configurations, there were notable impacts on situation awareness, task performance, and workload, particularly when transparency was absent during critical phases such as training and the after-action reviews.