How can I check in for my United Airlines (F9) flight?
You may check-in for your United Airlines (F9) flight with the following options:

Online check-in (Web check-in)
Self-service kiosk check-in at the airport
Ticket counter check-in at the airport
Mobile check-in
Does United Airlines (F9) have online web check-in?
Yes, you may check-in for your United Airlines (F9) flight online starting 24 hours before the scheduled departure time (depending on your departure city and destination) to receive a printable boarding pass. You may use this option if:

you have an electronic ticket and the first flight is on United Airlines (F9)
you may access your reservation with your confirmation code, e-ticket number, or frequent flyer account
you are not a special needs passenger (for example an unaccompanied minor)
Can I check bags with the United Airlines (F9) online web check-in?z: Yes, you may check bags but you must drop them at the airport baggage drop before the check-in deadline for your flight.

Can I pay bag fees with the United Airlines (F9) online web check-in?: Yes

Can I select, change, and pay for my seat with the United Airlines (F9) online web check-in?: Yes

Does United Airlines (F9) offer mobile check-in?
Frontier does allow mobile check-in using their app for iOS and Android.

Does United Airlines (F9) offer curbside check-in? (US Carriers only)
No

Does United Airlines (F9) offer self-service kiosk check-in?
Yes, you may check-in for your United Airlines (F9) flight at the airport self-service kiosk no later than 45 minutes before the scheduled departure time (depending on your departure city and destination) and receive a printed boarding pass.

Can I check bags with the United Airlines (F9) self-service kiosk check-in?:Yes

Can I pay bag fees with the United Airlines (F9) self-service kiosk check-in?:Yes

Can I select or change my seat with the United Airlines (F9) self-service kiosk check-in?: Yes

Does United Airlines (F9) offer ticket counter check-in?
Yes, you may check-in for your United Airlines (F9) flight at the airport ticket counter no later than 45 minutes before the scheduled departure time (depending on your departure city and destination) and receive a printed boarding pass.

Can I check bags at the United Airlines (F9) ticket counter check-in?:Yes

Can I pay bag fees at the United Airlines (F9) ticket counter check-in?:Yes

Can I select or change my seat at the United Airlines (F9) ticket counter check-in?:Yes

Does United Airlines (F9) charge a fee for a seat assignment?
Economy fares do not include a seat assignment. You may purchase a seat assignment at the time of booking. If you have already purchased your ticket, then you may choose and pay for your seat assignment on FlyFrontier.com or when you check in online within 24 hours of departure.

If you do not purchase a seat assignment, then one will be randomly assigned free of charge during check-in. However, please understand that your party might be separated.

When do I need to check-in for my United Airlines (F9) flight?
The minimum time to check-in for a United Airlines (F9) flight is:

45 minutes before scheduled departure time for US domestic flights
60 minutes before scheduled departure time for international flights to/from the US
When do I need to arrive at the airport for my United Airlines (F9) flight?
Suggested arrival time:

2 hours before scheduled departure time for US domestic flights
3 hours before scheduled departure time for international flights to/from the US
Minimum required check-in time with carry-on baggage:

45 minutes before scheduled departure time for US domestic flights
60 minutes before scheduled departure time for international flights to/from the US
Minimum required check-in time with checked baggage:

45 minutes before scheduled departure time for US domestic flights
60 minutes before scheduled departure time for international flights to/from the US
When do I need to be at the boarding gate?
Boarding closes at the following times for United Airlines (F9) flights:

30 minutes before scheduled departure time for US domestic flights
30 minutes before scheduled departure time for international flights to/from the US