Which Terminal is Southwest at PHX, Southwest Airlines operates out of Terminal 4 at Phoenix Sky Harbor International Airport (PHX). Located in the heart of the airport, Terminal 4 is Southwest’s main hub and offers a convenient and efficient travel experience for passengers. With its modern facilities and amenities, Terminal 4 provides a comfortable environment while you wait for your Southwest flight. From check-in to security to boarding gates, everything is conveniently located within this terminal, ensuring a seamless journey for Southwest passengers. So if you’re flying with Southwest Airlines from PHX, rest assured that you’ll find yourself in Terminal 4, ready to embark on your next adventure.