I have a 6:45 am flight on Tues June 1st. I will need to return my rental at about 5:00 am. I have not secured a rental yet. How can I get from the rental car return place to the terminal for my flight (Frontier) at that hour? Is there a shuttle?

You can drop the key on your car rental's return box. Then head in the car rental building, there you will find a screen with all the flights departing from DFW and their corresponding terminal. Find your flight from the screen and take the shuttle bus that matches your flight departing terminal.

Yes. 24/7

There is a shuttle that will take you. 24/7

Yes there is a bus that runs 24/7

thanks everyone. your answers have been very helpfull

Yes, the rental car center bus runs 24/7

There is a rental car shuttle that goes between the terminals and the rental car center. The airport is big and spread out, so please make sure you allow enough time for transit time. The shuttle will be stopping at different terminals along the route if there are others that need to be dropped off or picked up.

There are some shuttles there the last time I was ther