Follow the Steps Below to Upgrade Your Seat:
1. Open the Frontier Airlines mobile app and check-in for your flight.
2. At the allowed upgrade time, select "Manage" for your reservation. You can access your reservation on the homepage or under the "My Trips" tab.
3. Once you are in the Manage My Booking tab, select “Add seats, bags, or services”.
4. Select the pencil icon under the “Upgrade Your Seat Now” section.
5. Select your desired UpFront Plus or Premium seat. You will only be able to select available seats.
6. Elige continue at the bottom of the page.
7. You will be taken back to the Upgrade & Save page which will display your new seat assignment.