Originally Posted by guflyer

Thank you very much for your response, it is greatly appreciated. Upon searching the thread, I could not find the answer, but perhaps the search function did not work as well as intended. Whenever I have taken the TTB from T3 to T5, I have been asked to show both my boarding pass and my passport. So this made me wonder whether I would run into an issue if my boarding pass was for a domestic flight on Frontier.