Passengers flying with Frontier Airlines can check in at the counters located on the departure level of Terminal E. To save time, Frontier encourages travelers to check in online or use the self-service kiosks available in the terminal. Security checkpoints at Terminal E are typically quick, but it’s still best to arrive at least two hours before your flight to allow ample time. https://airportsterminalhub.com/airlines/frontier-airlines/frontier-airlines-dallas-fort-worth-international-airport-dfw-terminal/