You can change your departure time or date through the Frontier website or mobile app.
On the website:
• Go to My Trips/Check-In
• Enter your Last Name and Confirmation Code
• Click Search
• Select Change Flights and follow the prompts
In the app:
• Download the Frontier app from the iOS App Store or Google Play
• Tap the menu icon (three bars) in the top left
• Enter your Last Name and Confirmation Code
• Tap Retrieve
• Select Change Flight and follow the steps
Changes may be subject to fare differences or fees depending on your fare type. Be sure to review the total before confirming.