Can I check in online and still check a bag?

Yes. After checking in online, go to the bag drop counter at the airport (it's faster than the full check-in line). Show your boarding pass and ID, hand over your bag, and proceed to security.

Is a mobile boarding pass accepted everywhere?

Yes, at virtually all major airports in the US. Make sure your phone is charged. If you're concerned, take a screenshot as a backup or print your boarding pass as well.

What if I forget to check in online?

You can always check in at the airport counter or kiosk. It just means you'll spend a few more minutes at the airport. Some budget airlines charge fees for counter check-in, so online check-in is worth doing when possible.

How to Check In for a Flight Online

Q: When does online check-in open for most airlines?

Online check-in opens 24 hours before your scheduled departure for most major airlines including American, Delta, United, and JetBlue.

What Is Online Check-In?

Online check-in is the process of confirming your presence on a flight before you arrive at the airport. It's done through the airline's website or mobile app, and it's how you get your boarding pass without waiting at an airport counter. Almost every major airline offers it, and it's free.

When Does Online Check-In Open?

For most airlines, online check-in opens 24 hours before your scheduled departure time. This is the standard window used by American, Delta, United, Southwest, JetBlue, and most other major carriers.

A few exceptions:

Southwest Airlines: Check-in opens at exactly 24 hours before departure. Because Southwest doesn't assign seats, early check-in is critical — it determines your boarding group and position in line.
International flights: Check-in still opens 24 hours before, but some airlines close online check-in earlier (sometimes 60-90 minutes before departure) for international flights due to documentation verification requirements.
Budget carriers: Spirit and Frontier sometimes have different windows; check the airline's website for specifics.

Step-by-Step: How to Check In Online

Step 1: Download the Airline's App or Go to Their Website

The easiest way to check in is through the airline's mobile app. Most major airlines (American, Delta, United, Southwest, JetBlue, Alaska) have polished apps that handle check-in, boarding passes, flight tracking, and seat changes in one place. Alternatively, go to the airline's website directly.

Step 2: Find Your Booking

You'll need your confirmation number (also called a booking reference or record locator) — it's a 6-character alphanumeric code that looks like "HX7K4P". It's in your booking confirmation email. You'll also need the last name you booked with.

Enter these into the app or website's check-in section.

Step 3: Confirm Passenger Details

The system will show you your flight details and passenger information. Verify that your name matches your ID exactly. If anything is wrong, don't proceed — contact the airline to correct it first.

Step 4: Choose or Confirm Your Seat

If you haven't selected a seat yet, you'll have the opportunity here. Seat maps show available seats and sometimes their costs. Basic Economy tickets often restrict seat selection at check-in, assigning you a seat automatically.

Step 5: Answer Security Questions

For international flights especially, you may need to answer questions about your travel documents: passport number, nationality, date of birth, destination address. Have your passport handy.

Step 6: Get Your Boarding Pass

After completing check-in, you'll receive your boarding pass. You can:

Save it to your phone's wallet (Apple Wallet or Google Pay)
Screenshot it
Download the PDF and print it
Have the airline email it to you

The mobile boarding pass in your phone's wallet is the most convenient option. It updates automatically if your gate changes and doesn't require paper.

Do You Still Need to Go to the Check-In Counter?

If you're only traveling with a carry-on bag, you can skip the check-in counter entirely after checking in online. Head straight to security with your mobile boarding pass.

If you're checking a bag, go to the bag drop counter (not the full check-in line — bag drop moves faster). Show your boarding pass and ID, hand over your bag, and you're done. At many airports, there are also automated bag drop kiosks that let you tag and drop your bag without speaking to an agent.

What If Online Check-In Doesn't Work?

Common reasons online check-in fails:

Name mismatch: The name on your ticket doesn't match what you're entering
International documentation not verified: Some airlines require passport details before check-in opens
Overbooking flag: The airline may be managing an oversold flight
Special needs flag: If you requested wheelchair assistance or a special meal, some systems require agent verification
Technical issues: Try a different browser or device, or use the app instead of the website

If online check-in fails, arrive at the airport a little earlier and check in at the counter. It's not a big deal — the counter is always a valid option.

Online Check-In vs. Airport Check-In: Key Differences

Online Check-In	Airport Check-In
Free, done from home	Sometimes incurs fees (Spirit charges $25+ at counter)
Opens 24 hours before	Available at airport
You get your boarding pass ahead of time	Boarding pass printed at airport
Better for getting your preferred seat	Required if you need special assistance

Checking in for Multiple Passengers

If you booked multiple passengers on the same reservation, online check-in handles all of them at once. You'll be able to confirm each passenger's details, select seats for each, and download boarding passes for everyone in one go. Keep each person's boarding pass accessible on their own device, or print one per person.

The Bottom Line

Online check-in is faster, easier, and often cheaper than checking in at the airport. Do it as soon as the window opens — especially on Southwest where it affects your boarding position. Save your boarding pass to your phone's wallet app and you're ready to head to security without any counter stops.