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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From $140 / RT details

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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

Recent Deals on Flights from Ontario to Saint Louis:Roundtrip / Oneway

• $140 Frontier Airlines 

  From	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

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• $200 Frontier Airlines 

  From	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

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• $80 Frontier Airlines 

  From	To	Departure	Time
  Ontario, CA (ONT)	Saint Louis, MO (STL)	03/24/2025	12:59 am

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• $376 Frontier Airlines 

  From	To	Departure	Time
  Ontario, CA (ONT)	Saint Louis, MO (STL)	03/20/2025	04:39 pm

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