Cheap flights from Ontario to Saint Louis
Travel > North America > United States > Ontario to Saint Louis flights
Check our current prices for flights from Ontario to Saint Louis. Please note that we also give you historical search data for this city connection. These are all airfares that people found in the past, in order to find more current flight information from Ontario to Saint Louis, you will need to run a search below.
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Book your flight now with Cheapoair.com and save!
Cheap Saint Louis airfares from $140/RT are provided by Cheapoair.com. Outbound flight is leaving on 04/07/2025, 12:59 am from Ontario Int`l (ONT) airport and arrives at St. Louis Intl (STL) at 09:06 am. The flight time is 8 hours and 7 minutes. The Returning flight departes on 04/12/2025, 06:51 pm (other return dates are also available). Date posted: 11 Feb 2025
Price evolution for flights From Ontario To Saint Louis
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Recent Deals on Flights from Ontario to Saint Louis:Roundtrip / Oneway
- $140
Frontier Airlines
cheapoair.com check priceFrom To Departure Time Ontario, CA (ONT) Saint Louis, MO (STL) 04/07/2025 12:59 am Saint Louis, MO (STL) Ontario, CA (ONT) 04/12/2025 06:51 pm - $200
Frontier Airlines
cheapoair.com check priceFrom To Departure Time Ontario, CA (ONT) Saint Louis, MO (STL) 04/02/2025 02:43 pm Saint Louis, MO (STL) Ontario, CA (ONT) 04/16/2025 06:51 pm - $226
Frontier Airlines
cheapoair.com check priceFrom To Departure Time Ontario, CA (ONT) Saint Louis, MO (STL) 02/26/2025 12:59 am Saint Louis, MO (STL) Ontario, CA (ONT) 03/07/2025 07:09 pm - $266
Frontier Airlines
cheapoair.com check priceFrom To Departure Time Ontario, CA (ONT) Saint Louis, MO (STL) 03/03/2025 09:06 pm Saint Louis, MO (STL) Ontario, CA (ONT) 03/08/2025 07:04 pm - $510
Frontier Airlines
cheapoair.com check priceFrom To Departure Time Ontario, CA (ONT) Saint Louis, MO (STL) 03/17/2025 12:59 am Saint Louis, MO (STL) Ontario, CA (ONT) 03/28/2025 06:38 pm - $66
Frontier Airlines
cheapoair.com check priceFrom To Departure Time Ontario, CA (ONT) Saint Louis, MO (STL) 02/24/2025 02:43 pm - $80
Frontier Airlines
cheapoair.com check priceFrom To Departure Time Ontario, CA (ONT) Saint Louis, MO (STL) 03/24/2025 12:59 am - $81
Frontier Airlines
cheapoair.com check priceFrom To Departure Time Ontario, CA (ONT) Saint Louis, MO (STL) 03/13/2025 04:39 pm - $94
Frontier Airlines
cheapoair.com check priceFrom To Departure Time Ontario, CA (ONT) Saint Louis, MO (STL) 03/14/2025 12:59 am - $376
Frontier Airlines
cheapoair.com check priceFrom To Departure Time Ontario, CA (ONT) Saint Louis, MO (STL) 03/20/2025 04:39 pm
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Know what to do when flying to Saint Louis?
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