- What terminal is Frontier Airlines at IAH refers to the specific terminal that Frontier Airlines operates from at George Bush Intercontinental Airport (IAH) in Houston, Texas. The answer to What terminal is Frontier Airlines at IAH is Terminal A. This is where passengers flying with Frontier Airlines check in, pass through security, and board their flights. Knowing the correct terminal is essential for a smooth airport experience, and for those traveling with Frontier Airlines at IAH, Terminal A is the designated location for all flight operations.