$28 Cheap Flights to O'Fallon, IL

View $28 flight on Wed, Jun 17, 2026Opens in a new window

Popular airlines to O'Fallon

How much is the cheapest flight to O'Fallon?

Prices were available within the past 7 days and start at $28 for one-way flights and $56 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Wed, Jun 17 - Tue, Jun 23
DEN
Denver
STL
St. Louis
$56 Roundtrip, found 1 hour ago
$56
Roundtrip
found 1 hour ago
Select Frontier Airlines flight, departing Wed, Jun 17 from Denver to St. Louis, returning Tue, Jun 23, priced at $56 found 1 hour ago
United
Wed, Jun 24 - Tue, Jun 30
DEN
Denver
STL
St. Louis
$201 Roundtrip, found 1 hour ago
$201
Roundtrip
found 1 hour ago
Select United flight, departing Wed, Jun 24 from Denver to St. Louis, returning Tue, Jun 30, priced at $201 found 1 hour ago
Southwest Airlines
Wed, Jun 24 - Tue, Jun 30
DEN
Denver
STL
St. Louis
$201 Roundtrip, found 1 hour ago
$201
Roundtrip
found 1 hour ago
Select Southwest Airlines flight, departing Wed, Jun 24 from Denver to St. Louis, returning Tue, Jun 30, priced at $201 found 1 hour ago
American Airlines
Tue, Jun 16 - Tue, Jun 23
DEN
Denver
STL
St. Louis
$221 Roundtrip, found 10 hours ago
$221
Roundtrip
found 10 hours ago
Select American Airlines flight, departing Tue, Jun 16 from Denver to St. Louis, returning Tue, Jun 23, priced at $221 found 10 hours ago
Delta
Wed, Jun 10 - Tue, Jun 16
DEN
Denver
STL
St. Louis
$221 Roundtrip, found 1 hour ago
$221
Roundtrip
found 1 hour ago
Select Delta flight, departing Wed, Jun 10 from Denver to St. Louis, returning Tue, Jun 16, priced at $221 found 1 hour ago

Alternative airports near O'Fallon

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Lambert-St. Louis Intl. STL. Cheapest option available. Average driving time to city center is 36 minutes. Flights from $325
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center36 min
Flights from $325

Frequently asked questions

What month is the cheapest to fly to O'Fallon?
Schedule your trip for June if you're hoping to get a good price on your fare. It's the cheapest month to fly to O'Fallon. Try to avoid traveling during busy periods such as public holidays or major events.
Which US cities have the cheapest flights to O'Fallon?
Score cheap flights to O'Fallon from Chicago, Dallas and Denver. These cities typically offer the lowest fares to this top destination. But keep in mind that stopovers, seasonality and demand will also influence rates, so remain flexible and book when you see a bargain.
Which US cities fly direct to O'Fallon?
Pick from 55 US cities that have direct flights to O'Fallon. When booking on Expedia, select the "Direct flights only" box to compare nonstop routes. Fly to O'Fallon from any of these top cities:

  • Chicago
  • Dallas
  • Denver
  • New York
  • Atlanta

How to find a cheap flight to O'Fallon?
Book your trip early to score cheap flights to O'Fallon. Also, consider traveling during off-season months like December and January. If you jet off on a Thursday, you'll save an average of 16% compared to those departing on a Sunday.* Save time checking every day and track your flight prices using the Expedia app. We'll update you when fares change.*Best day of the week to book, depart and ideal booking window recommendations based on average round-trip ticket prices for January through August 2023, sourced from Airline Reporting Corporation's (ARC) global airline sales database. Percentages noted are averages.
How to get a cheap last-minute flight to O'Fallon?
Being flexible with your plans might help you find last-minute offers on cheap flights to O'Fallon. To see all the available options, try exploring different ticket types, changing your O'Fallon trip dates, leaving from an alternative airport or using another carrier.
How far in advance should I book a flight to O'Fallon?
Book your flight to O'Fallon two to four months ahead if you're flying in from an international destination. For domestic travel, the recommendation is around 28 days in advance. Cheaper fares and a wider variety of travel dates, times and seating options are just some of the perks of booking early.**Best day of the week to book, depart and ideal booking window recommendations based on average round-trip ticket prices for January through August 2023, sourced from Airline Reporting Corporation's (ARC) global airline sales database. Percentages noted are averages.
Which day of the week is the cheapest day to buy a plane ticket to O'Fallon?
You can save an average of 8% if you buy tickets on a Sunday instead of Fridays, which tend to be the most expensive day to book.* When it comes to snapping up a cheap flight to O'Fallon, timing makes a difference.*Best day of the week to book, depart and ideal booking window recommendations based on average round-trip ticket prices for January through August 2023, sourced from Airline Reporting Corporation's (ARC) global airline sales database. Percentages noted are averages.
Which airlines fly to O'Fallon?
There are 10 carriers connecting O'Fallon with 33 airports across the world. The chief entry point to this city is Lambert-St. Louis Intl. Airport (STL). Book a ticket with any of these leading airlines to O'Fallon:

  • Delta Air Lines
  • American Airlines
  • United Airlines
  • Southern Airways Express

Where do you fly into O'Fallon?
If you're flying to O'Fallon, the main airport for arrivals is Lambert-St. Louis Intl. Airport (STL). You can also head for nearby hubs like MidAmerica-St. Louis Airport (BLV), St. Louis Downtown Airport (CPS) or Spirit of St. Louis Airport (SUS). Another good option to think about when you fly to O'Fallon is Vandalia, IL (VLA-Vandalia Municipal).
How far is the airport from central O'Fallon?
If you're touching down at Lambert-St. Louis Intl. Airport (STL), you'll be around 25 mi northwest of the center of O'Fallon.
Can I save money by booking an O'Fallon trip package?
Book an O'Fallon flight and hotel package deal on Expedia, and you can make significant savings. It's easy to bundle your flight and hotel, and you can also add car rentals and activities to create your own personalized O'Fallon vacation. Plus, nothing beats the convenience of booking everything in the same place.
Can I change or cancel my flight to O'Fallon?
If you booked your flight to O'Fallon within the last 24 hours, you can typically cancel or change it without fees. After that, additional charges may apply depending on the airline's rules and restrictions. For more information, head to our Customer Service Portal. Remember that some flights are non-refundable, so you may receive a credit toward a future flight in place of a direct refund. When browsing Expedia, select the "No cancel fee" or "Changes included" filters to find tickets with flexible change policies.

*Flight schedules are subject to change.

*Available to One Key members.

 

Travel information

Destination airport
Lambert-St. Louis Intl.
Destination airport IATA code
STL
Destination city name
St. Louis
Roundtrip price
$56

Trending flights to O'Fallon

Prices were available within the past 7 days and start at $28 for one-way flights and $56 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Wed, Jun 17 - Tue, Jun 23
DEN
Denver
STL
St. Louis
$56 Roundtrip, found 1 hour ago
$56
Roundtrip
found 1 hour ago
Select Frontier Airlines flight, departing Wed, Jun 17 from Denver to St. Louis, returning Tue, Jun 23, priced at $56 found 1 hour ago

Explore a world of travel with Expedia